SlideShare ist ein Scribd-Unternehmen logo
1 von 24
DIFFERENTIAL EQUATION II
TASK COMPILATION
3/27/2014
MARIA PRISCILLYA PASARIBU
IDN. 4103312018
TASK I (February, 13th 2014)
Determine the solution of::
1.
𝑑2 𝑦
𝑑𝑑2
βˆ’ 2
𝑑𝑦
𝑑𝑑
βˆ’ 5𝑦 = 0, y(0)=0; y’(0)=1
2.
𝑑2 𝑦
𝑑𝑑2
βˆ’ 3
𝑑𝑦
𝑑𝑑
= 0, y(0)=0; y’(0)=1
3.
𝑑2 𝑦
𝑑𝑑2
βˆ’ 4
𝑑𝑦
𝑑𝑑
βˆ’ 4𝑦 = 0, y(0)=0; y’(0)=1
Solution:
1.
𝑑2 𝑦
𝑑𝑑2 βˆ’ 2
𝑑𝑦
𝑑𝑑
βˆ’ 5𝑦 = 0, y(0)=0; y’(0)=1
Characteristic Equation: πœ†2
βˆ’ 2πœ† βˆ’ 5 = 0
πœ†1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
=
βˆ’(βˆ’2) Β± √(βˆ’2)2 βˆ’ 4(1)(βˆ’5)
2(1)
=
2 ± √4 + 20
2
=
2 ± √24
2
=
2 ± 2√6
2
= 1 ± √6
πœ†1and πœ†2 are real and distinct, then 𝑦 = 𝑐1 𝑒 π‘š1 π‘₯
+ 𝑐2 𝑒 π‘š2 π‘₯
𝑦(0) = 0
0 = 𝑐1 + 𝑐2
𝑐1 = βˆ’π‘2 .................... (1)
𝑦′(0) = 1
𝑦′(π‘₯) = (1 + √6)𝑐1 𝑒(1+√6)π‘₯
+ (1 βˆ’ √6)𝑐1 𝑒(1βˆ’βˆš6)π‘₯
1 = (1 + √6)𝑐1 + (1 βˆ’ √6)𝑐2
1 = (1 + √6)𝑐1 + (1 βˆ’ √6)(βˆ’π‘1)
1 = 𝑐1(1 + √6 βˆ’ 1 + √6)
1 = 2√6𝑐1
𝑐1 =
1
12
√6
𝑐1 = βˆ’π‘2 .................... (1)
𝑐2 = βˆ’
1
12
√6
Maka, 𝑦 =
1
12
√6𝑒(1+√6)π‘₯
βˆ’
1
12
√6𝑒(1βˆ’βˆš6)π‘₯
2.
𝑑2 𝑦
𝑑𝑑2
βˆ’ 3
𝑑𝑦
𝑑𝑑
= 0, y(0)=0; y’(0)=1
Characteristic Equation:πœ†2
βˆ’ 3πœ† = 0
πœ†(πœ† βˆ’ 3) = 0
πœ†1 = 0 ∨ πœ†2 = 3
πœ†1and πœ†2 are real and distinct, then 𝑦 = 𝑐1 𝑒 π‘š1 π‘₯
+ 𝑐2 𝑒 π‘š2 π‘₯
𝑦 = 𝑐1 𝑒0π‘₯
+ 𝑐2 𝑒3π‘₯
𝑦(0) = 0
0 = 𝑐1 + 𝑐2
𝑐1 = βˆ’π‘2 .................... (1)
𝑦′(0) = 1
𝑦′(π‘₯) = 3𝑐2
3π‘₯
1 = 3𝑐2
𝑐2 =
1
3
𝑐1 = βˆ’
1
3
Then, 𝑦 = βˆ’
1
3
𝑒 π‘š1 π‘₯
+
1
3
𝑒 π‘š2 π‘₯
3.
𝑑2 𝑦
𝑑𝑑2
βˆ’ 4
𝑑𝑦
𝑑𝑑
βˆ’ 4𝑦 = 0, y(0)=0; y’(0)=1
Characteristic Equation:πœ†2
βˆ’ 4πœ† βˆ’ 4 = 0
πœ†1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
=
βˆ’(βˆ’4) Β± √(βˆ’4)2 βˆ’ 4(1)(βˆ’4)
2(1)
=
4 ± √16 + 16
2
=
4 ± 4√2
2
= 2 ± 2√2
πœ†1and πœ†2 are real and distinct, then 𝑦 = 𝑐1 𝑒 π‘š1 π‘₯
+ 𝑐2 𝑒 π‘š2 π‘₯
𝑦 = 𝑐1 𝑒(2+2√2)π‘₯
+ 𝑐2 𝑒(2βˆ’2√2)π‘₯
𝑦(0) = 0
0 = 𝑐1 + 𝑐2
𝑐1 = βˆ’π‘2 .................... (1)
𝑦′(0) = 1
𝑦′(π‘₯) = (2 + 2√2)𝑐1 𝑒(2+2√2)π‘₯
+ (2 βˆ’ 2√2)𝑐2 𝑒(2βˆ’2√2)π‘₯
1 = (2 + 2√2)𝑐1 + (2 βˆ’ 2√2)𝑐2
1 = (2 + 2√2)𝑐1 + (2 βˆ’ 2√2)(βˆ’π‘1)
1 = 𝑐1(2 + 2√2 βˆ’ 2 + 2√2)
1 = 𝑐1(4√2)
𝑐1 =
1
8
√2
𝑐1 = βˆ’π‘2 .................... (1)
𝑐2 = βˆ’
1
8
√2
Maka,
𝑦 =
1
8
√2𝑒(2+2√2)π‘₯
βˆ’
1
8
√2𝑒(2βˆ’2√2)π‘₯
TASK II (February, 20th 2014)
Solve these equation:
1.
𝑑4 𝑦
𝑑π‘₯4
+ 10
𝑑2 𝑦
𝑑π‘₯2
+ 9𝑦 = 0
2.
𝑑4 𝑦
𝑑π‘₯4 +
𝑑3 𝑦
𝑑π‘₯3 +
𝑑2 𝑦
𝑑π‘₯2 + 2𝑦 = 0
3. 𝑦′′′
+ 4𝑦′
= 0
4. 𝑦(4)
+ 4𝑦′′
βˆ’ 𝑦′
+ 6𝑦 = 0
5.
𝑑6 𝑦
𝑑π‘₯6
βˆ’ 4
𝑑5 𝑦
𝑑π‘₯5
+ 16
𝑑4 𝑦
𝑑π‘₯4
βˆ’ 12
𝑑3 𝑦
𝑑π‘₯3
+ 41
𝑑2 𝑦
𝑑π‘₯2
βˆ’ 8
𝑑𝑦
𝑑π‘₯
+ 26𝑦 = 0
Solution:
1.
𝑑4 𝑦
𝑑π‘₯4
+ 10
𝑑2 𝑦
𝑑π‘₯2
+ 9𝑦 = 0
Characteristic equation: πœ†4
+ 10πœ†2
+ 9 = 0
(πœ†2
+ 9)(πœ†2
+ 1) = 0
(πœ† + 3𝑖)(πœ† βˆ’ 3𝑖)(πœ† + 𝑖)(πœ† βˆ’ 𝑖) = 0
πœ†1 = βˆ’3𝑖 ⋁ πœ†2 = βˆ’3𝑖 ⋁ πœ†3 = βˆ’π‘– ⋁ πœ†3 = 𝑖
So, the solution is 𝑦 = 𝐢1 cos 3π‘₯ + 𝐢2 sin 3π‘₯ + 𝐢3 cos π‘₯ + 𝐢4 sin π‘₯
2.
𝑑4 𝑦
𝑑π‘₯4
+
𝑑3 𝑦
𝑑π‘₯3
+
𝑑2 𝑦
𝑑π‘₯2
+ 2𝑦 = 0
Characteristic equation: πœ†4
+ πœ†3
+ πœ†2
+ 2 = 0
(πœ†2
βˆ’ πœ† + 1)(πœ†2
+ 2πœ† + 2) = 0
ο‚· (πœ†2
βˆ’ πœ† + 1) = 0
πœ†1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†1,2 =
βˆ’(βˆ’1) Β± √(βˆ’1)2 βˆ’ 4(1)(1)
2(1)
πœ†1,2 =
1 Β± √1 βˆ’ 4
2
πœ†1,2 =
1 Β± √3𝑖
2
πœ†1 =
1
2
+
1
2
√3𝑖 and πœ†2 =
1
2
βˆ’
1
2
√3𝑖
ο‚· (πœ†2
+ 2πœ† + 2) = 0
πœ†3,4 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†3,4 =
βˆ’(2) Β± √(2)2 βˆ’ 4(1)(2)
2(1)
πœ†3,4 =
βˆ’2 Β± √4 βˆ’ 8
2
πœ†3,4 =
βˆ’2 Β± 2𝑖
2
πœ†3 = βˆ’1 + 𝑖 and πœ†4 = βˆ’1 βˆ’ 𝑖
So, the solution is 𝑦 = 𝑒
1
2
π‘₯
(𝐢1 cos
1
2
√3π‘₯ + 𝐢2 sin
1
2
√3π‘₯) + π‘’βˆ’π‘₯
(𝐢3 cos π‘₯ +
𝐢4 sin π‘₯)
3. 𝑦′′′
+ 4𝑦′
= 0
Characteristic equation: πœ†3
+ 4πœ† = 0
πœ†(πœ†2
+ 4) = 0
πœ†(πœ† + 2𝑖)(πœ† βˆ’ 2𝑖) = 0
πœ†1 = 0 ⋁ πœ†2 = βˆ’2𝑖 ⋁ πœ†3 = 2𝑖
So, the solution is 𝑦 = 𝐢1 + 𝐢2cos2π‘₯ + 𝐢3 sin 2π‘₯
4. 𝑦(4)
+ 4𝑦′′
βˆ’ 𝑦′
+ 6𝑦 = 0
Characteristics equation is πœ†4
+ 4πœ†2
βˆ’ πœ† + 6 = 0
(πœ†2
βˆ’ πœ† + 2)(πœ†2
+ πœ† + 3) = 0
ο‚· (πœ†2
βˆ’ πœ† + 2) = 0
πœ†1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†1,2 =
βˆ’(βˆ’1) Β± √(βˆ’1)2 βˆ’ 4(1)(2)
2(1)
πœ†1,2 =
1 Β± √1 βˆ’ 8
2
πœ†1,2 =
1 Β± √7𝑖
2
πœ†1 =
1
2
+
1
2
√7𝑖 and πœ†2 =
1
2
βˆ’
1
2
√7𝑖
ο‚· (πœ†2
+ πœ† + 3) = 0
πœ†3,4 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†3,4 =
βˆ’(1) Β± √(1)2 βˆ’ 4(1)(3)
2(1)
πœ†3,4 =
βˆ’1 Β± √1 βˆ’ 12
2
πœ†3,4 =
βˆ’1 Β± √11𝑖
2
πœ†3 = βˆ’
1
2
+
1
2
√11𝑖 and πœ†4 = βˆ’
1
2
βˆ’
1
2
√11𝑖
So, the equation is:
𝑦 = 𝑒
1
2
π‘₯
(𝐢1 cos
1
2
√7π‘₯ + 𝐢2 sin
1
2
√7π‘₯) + π‘’βˆ’
1
2
π‘₯
(𝐢3 cos
1
2
√11 π‘₯ + 𝐢4 sin
1
2
√11 π‘₯)
5.
𝑑6 𝑦
𝑑π‘₯6
βˆ’ 4
𝑑5 𝑦
𝑑π‘₯5
+ 16
𝑑4 𝑦
𝑑π‘₯4
βˆ’ 12
𝑑3 𝑦
𝑑π‘₯3
+ 41
𝑑2 𝑦
𝑑π‘₯2
βˆ’ 8
𝑑𝑦
𝑑π‘₯
+ 26𝑦 = 0
Characteristic equation is πœ†6
βˆ’ 4πœ†5
+ 16πœ†4
βˆ’ 12πœ†3
+ 41πœ†2
βˆ’ 8πœ† + 26 = 0
(πœ†4
+ 3πœ†2
+ 2)(πœ†2
βˆ’ 4πœ† + 13) = 0
(πœ†2
+ 1)(πœ†2
+ 2)(πœ†2
βˆ’ 4πœ† + 13) = 0
ο‚· (πœ†2
+ 1) = 0
πœ†1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†1,2 =
0 Β± √0 βˆ’ 4(1)(1)
2(1)
πœ†1,2 =
Β±βˆšβˆ’4
2
πœ†1,2 =
Β±2𝑖
2
πœ†1 = 𝑖 and πœ†2 = βˆ’π‘–
ο‚· (πœ†2
+ 2) = 0
πœ†3,4 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†3,4 =
0 Β± √0 βˆ’ 4(1)(2)
2(1)
πœ†3,4 =
Β±βˆšβˆ’8
2
πœ†3,4 =
Β±2√2𝑖
2
πœ†3 = √2𝑖 and πœ†4 = βˆ’βˆš2𝑖
ο‚· (πœ†2
βˆ’ 4πœ† + 13) = 0
πœ†5,6 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†5,6 =
βˆ’(βˆ’4) Β± √(βˆ’4)2 βˆ’ 4(1)(13)
2(1)
πœ†5,6 =
4 Β± √16 βˆ’ 52
2
πœ†5,6 =
4 Β± 6𝑖
2
πœ†5 = 2 + 3𝑖 and πœ†6 = 2 βˆ’ 3𝑖
So, the solution is 𝑦 = 𝐢1 cos π‘₯ + 𝐢1 sin π‘₯ + 𝑒2π‘₯(𝐢3 cos 3π‘₯ + 𝐢4 sin 3π‘₯) +
𝐢5 cos √2π‘₯ + 𝐢5 sin √2π‘₯
TASK III (March 7th, 2014)
1.
𝑑3 π‘ž
𝑑𝑑3
βˆ’ 5
𝑑2 π‘ž
𝑑𝑑2
+ 25
π‘‘π‘ž
𝑑𝑑
βˆ’ 125π‘ž = βˆ’60𝑒7𝑑
y(0)=0, y’(0)=1, y”(0)=2
2. 𝑦(𝐼𝑉)
βˆ’ 6𝑦′′′
+ 16𝑦′′
+ 54𝑦′
βˆ’ 225𝑦 = 100π‘’βˆ’2π‘₯
𝑦(0) = 𝑦′(0) = 𝑦′′(0) = 𝑦′′′(0) = 1
Solution:
1.
𝑑3 π‘ž
𝑑𝑑3 βˆ’ 5
𝑑2 π‘ž
𝑑𝑑2 + 25
π‘‘π‘ž
𝑑𝑑
βˆ’ 125π‘ž = βˆ’60𝑒7𝑑
y(0)=0, y’(0)=1, y”(0)=2
Quadratic equation: πœ†3
βˆ’ 5πœ†2
+ 25πœ† βˆ’ 125 = βˆ’60𝑒7𝑑
Y= yl + yr
πœ†3
βˆ’ 5πœ†2
+ 25πœ† βˆ’ 125 = 0
(πœ† βˆ’ 5)(πœ† + 5𝑖)(πœ† βˆ’ 5𝑖) = 0
𝑦𝑙 = 𝑐1 𝑒5𝑑
+ 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑
π‘¦π‘Ÿ = 𝐴0 𝑒7𝑑
π‘¦π‘Ÿ
β€²
= 7𝐴0 𝑒7𝑑
π‘¦π‘Ÿ
β€²β€²
= 49𝐴0 𝑒7𝑑
π‘¦π‘Ÿ
β€²β€²β€²
= 343𝐴0 𝑒7𝑑
𝑦′′′
βˆ’ 5𝑦′′
+ 25𝑦 βˆ’ 125𝑦 = βˆ’60𝑒7𝑑
343𝐴0 𝑒7𝑑
βˆ’ 245𝐴0 𝑒7𝑑
+ 175𝐴0 𝑒7𝑑
βˆ’ 125𝐴0 𝑒7𝑑
= βˆ’60𝑒7𝑑
148𝐴0 𝑒7𝑑
= βˆ’60𝑒7𝑑
𝐴0 = βˆ’
60
148
= βˆ’
15
37
π‘¦π‘Ÿ = βˆ’
15
37
𝑒7𝑑
Then, we got the equation is equal to
Y= yl + yr
𝑦(𝑑) = 𝑐1 𝑒5𝑑
+ 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑 βˆ’
15
37
𝑒7𝑑
Now, we are going to find the value of c1, c2, and c3.
y(0)=0
0 = 𝑐1 + 𝑐2 βˆ’
15
37
𝑐1 + 𝑐2 =
15
37
........................................ (1)
y’(0)=1
𝑦′
(𝑑) = 5𝑐1 𝑒5𝑑
βˆ’ 5𝑐2 sin 5𝑑 + 5𝑐3 cos 5𝑑 βˆ’
105
37
𝑒7𝑑
1 = 5𝑐1 + 5𝑐3 βˆ’
105
37
𝑐1 + 𝑐3 =
142
185
.................................... (2)
y”(0)=2
𝑦′′
(𝑑) = 25𝑐1 𝑒5𝑑
βˆ’ 25𝑐2 cos 5𝑑 βˆ’ 25𝑐3 sin 5𝑑 βˆ’
735
37
𝑒7𝑑
2 = 25𝑐1 βˆ’ 25𝑐2 βˆ’
735
37
25𝑐1 βˆ’ 25𝑐2 =
809
37
𝑐1 βˆ’ 𝑐2 =
809
925
....................................... (3)
Elimination of 𝑐2 from (1) and (3)
𝑐1 βˆ’ 𝑐2 =
809
925
....................................... (3)
𝑐1 + 𝑐2 =
15
37
........................................ (1)
2𝑐1 =
809 + 375
925
𝑐1 =
592
925
From (3), we can get the value of c2 by substituting the value of c1.
𝑐1 βˆ’ 𝑐2 =
809
925
....................................... (3)
+
592
925
βˆ’ 𝑐2 =
809
925
𝑐2 = βˆ’
217
925
From (2), we can get the value of c3 by substituting the value of c1.
𝑐1 + 𝑐3 =
142
185
.................................... (2)
592
925
+ 𝑐3 =
142
185
𝑐3 =
118
925
After getting the value of c1, c2, and c3, then the equation is:
𝑦(𝑑) =
592
925
𝑒5𝑑
βˆ’
217
925
cos 5𝑑 +
118
925
sin 5𝑑 βˆ’
15
37
𝑒7𝑑
2. 𝑦(𝐼𝑉)
βˆ’ 6𝑦′′′
+ 16𝑦′′
+ 54𝑦′
βˆ’ 225𝑦 = 100π‘’βˆ’2π‘₯
𝑦(0) = 𝑦′(0) = 𝑦′′(0) = 𝑦′′′(0) = 1
Quadratic equation: πœ†4
βˆ’ 6πœ†3
+ 16πœ†2
+ 54πœ† βˆ’ 225 = 100π‘’βˆ’2π‘₯
𝑦 = 𝑦𝑙 + π‘¦π‘Ÿ
πœ†4
βˆ’ 6πœ†3
+ 16πœ†2
+ 54πœ† βˆ’ 225 = 0
By using Horner method and ABC formula, so that the roots are gotten:
πœ†1 = 3 πœ†3 = 3 + 4𝑖
πœ†2 = βˆ’3 πœ†4 = 3 βˆ’ 4𝑖
𝑦𝑙 = 𝑐1 𝑒3𝑑
+ 𝑐2 π‘’βˆ’3𝑑
+ 𝑒3𝑑
(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑)
π‘¦π‘Ÿ = 𝐴0 π‘’βˆ’2π‘₯
π‘¦π‘Ÿ
β€²
= βˆ’2𝐴0 π‘’βˆ’2𝑑
π‘¦π‘Ÿ
β€²β€²
= 4𝐴0 π‘’βˆ’2𝑑
π‘¦π‘Ÿ
β€²β€²β€²
= βˆ’8𝐴0 π‘’βˆ’2𝑑
π‘¦π‘Ÿ
(𝐼𝑉)
= 16𝐴0 π‘’βˆ’2𝑑
𝑦(𝐼𝑉)
βˆ’ 6𝑦′′′
+ 16𝑦′′
+ 54𝑦′
βˆ’ 225𝑦 = 100π‘’βˆ’2𝑑
16𝐴0 π‘’βˆ’2𝑑
+ 48𝐴0 π‘’βˆ’2𝑑
+ 64𝐴0 π‘’βˆ’2𝑑
βˆ’ 108𝐴0 π‘’βˆ’2𝑑
βˆ’ 225𝐴0 π‘’βˆ’2𝑑
= 100π‘’βˆ’2𝑑
βˆ’205𝐴0 π‘’βˆ’2𝑑
= 100π‘’βˆ’2𝑑
𝐴0 = βˆ’
100
205
= βˆ’
20
41
So, the value of yr is
π‘¦π‘Ÿ = βˆ’
20
41
π‘’βˆ’2𝑑
𝑦 = 𝑐1 𝑒3𝑑
+ 𝑐2 π‘’βˆ’3𝑑
+ 𝑒3𝑑
(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) βˆ’
20
41
π‘’βˆ’2𝑑
Now, we are going to find the value of c1, c2, and c3.
y(0) = 1
1 = 𝑐1 + 𝑐2 + 𝑐3 βˆ’
20
41
𝑐1 + 𝑐2 + 𝑐3 =
61
41
....................................... (1)
y’(0)=1
𝑦′
= 3𝑐1 𝑒3𝑑
βˆ’ 3𝑐2 π‘’βˆ’3𝑑
+ 3𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) + 𝑒3𝑑(βˆ’4𝑐3 sin 4𝑑 + 4𝑐4 cos 4𝑑)
+
40
41
π‘’βˆ’2𝑑
1 = 3𝑐1 βˆ’ 3𝑐2 + 3𝑐3 + 4𝑐4 +
40
41
3𝑐1 βˆ’ 3𝑐2 + 3𝑐3 + 4𝑐4 =
1
41
........................ (2)
y’’(0)=1
𝑦′′
= 9𝑐1 𝑒3𝑑
+ 9𝑐2 π‘’βˆ’3𝑑
+ 9𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) + 3𝑒3𝑑(βˆ’4𝑐3 sin 4𝑑 + 4𝑐4 cos 4𝑑) +
3𝑒3𝑑(βˆ’4𝑐3 sin 4𝑑 + 4𝑐4 cos 4𝑑) βˆ’ 16𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) +
80
41
π‘’βˆ’2𝑑
1 = 9𝑐1 + 9𝑐2 + 9𝑐3 + 12𝑐4 + 12𝑐4 βˆ’ 16𝑐3 βˆ’
80
41
1 = 9(𝑐1 + 𝑐2 + 𝑐3) + 24𝑐4 βˆ’ 16𝑐3 βˆ’
80
41
121
41
= 9(
61
41
) + 24𝑐4 βˆ’ 16𝑐3
βˆ’
428
41
= 24𝑐4 βˆ’ 16𝑐3
2𝑐3 βˆ’ 3𝑐4 =
107
82
.......................................... (3)
y’’’(0)=1
𝑦′′′
= 27𝑐1 𝑒3𝑑
βˆ’ 27𝑐2 π‘’βˆ’3𝑑
+ 75𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) βˆ’ 100𝑒3𝑑(βˆ’π‘3 sin 4𝑑 +
𝑐4 cos 4𝑑) +
160
41
π‘’βˆ’2𝑑
1 = 27𝑐1 βˆ’ 27𝑐2 + 75𝑐3 βˆ’ 100𝑐4 +
160
41
27𝑐1 βˆ’ 27𝑐2 + 75𝑐3 βˆ’ 100𝑐4 = βˆ’
119
41
........ (4)
To get the value of c1, c2, c3, and c4, we can use elimination and substituion method from the
above equations.
From (4) and (2), we can get the new equation:
27𝑐1 βˆ’ 27𝑐2 + 75𝑐3 βˆ’ 100𝑐4 = βˆ’
119
41
........ (4)
27𝑐1 βˆ’ 27𝑐2 + 27𝑐3 + 36𝑐4 =
9
41
................ (2)
43𝑐3 βˆ’ 136𝑐4 = βˆ’
128
41
6𝑐3 βˆ’ 176𝑐4 = βˆ’
16
41
..................................... (5)
From (5) and (3), we can get the value of c4.
+
6𝑐3 βˆ’ 176𝑐4 = βˆ’
16
41
..................................... (5)
6𝑐3 βˆ’ 9𝑐4 =
321
82
... ....................................... (3)
βˆ’8𝑐4 =
βˆ’32 βˆ’ 321
82
𝑐4 =
βˆ’353
656
From (3), we can get the value of c3.
2𝑐3 βˆ’ 3(
βˆ’353
656
) =
107
82
.......................................... (3)
2𝑐3 =
1915
656
𝑐3 =
1915
1315
From (1), we get:
𝑐1 + 𝑐2 +
1915
1315
=
61
41
....................................... (1)
𝑐1 + 𝑐2 =
37
1312
................................................ (6)
From (2), we get:
3𝑐1 βˆ’ 3𝑐2 + 3(
1915
1315
) + 4(
βˆ’353
656
) =
1
41
........................ (2)
3𝑐1 βˆ’ 3𝑐2 =
32 βˆ’ 5745 βˆ’ 2824
1312
3𝑐1 βˆ’ 3𝑐2 = βˆ’
8537
1312
𝑐1 βˆ’ 𝑐2 = βˆ’
8537
3936
................................................ (7)
From (6) and (7), we can get the value of c1 and c2 by elimination method.
𝑐1 + 𝑐2 =
37
1312
................................................ (6)
+
𝑐1 βˆ’ 𝑐2 = βˆ’
8537
3936
............................................. (7)
2𝑐1 =
βˆ’8537 + 111
3936
2𝑐1 =
βˆ’8426
3936
𝑐1 =
βˆ’4213
3936
From (7), we can get the value of c2.
βˆ’4213
3936
βˆ’ 𝑐2 = βˆ’
8537
3936
............................................. (7)
𝑐2 =
8537 βˆ’ 4213
3936
𝑐2 =
1081
656
After getting the value of c1, c2, c3, and c4, we get the characteristic value.
𝑦 = βˆ’
4213
3936
𝑒3𝑑
+
1081
656
π‘’βˆ’3𝑑
+ 𝑒3𝑑
(
1915
1315
cos 4𝑑 βˆ’
353
656
sin 4𝑑) βˆ’
20
41
π‘’βˆ’2𝑑
+
TASK IV (March 13th, 2014)
1.
𝑑2 π‘ž
𝑑𝑑2
+ 1000
π‘‘π‘ž
𝑑𝑑
+ 25000π‘ž = 24
π‘ž(0) = π‘žβ€²(0) = 0
2.
𝑑2 𝑦
𝑑𝑑2
βˆ’ 4
𝑑𝑦
𝑑𝑑
+ 𝑦 = 2𝑑3
+ 3𝑑2
βˆ’ 1
𝑦(0) = 𝑦′(0) = 1
Solution:
1. π‘žβ€²β€² + 1000π‘žβ€² + 25000π‘ž = 24
Quadratic equation:
𝑑2
+ 1000𝑑 + 25000 = 0
𝑑1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
𝑑1,2 =
βˆ’1000 Β± √(1000)2 βˆ’ 4(1)(25000)
2(1)
𝑑1,2 =
βˆ’1000 Β± √900000
2
𝑑1,2 =
βˆ’1000 Β± 300√10
2
𝑑1,2 = βˆ’500 Β± 150√10
𝑑1 = βˆ’500 + 150√10 and 𝑑2 = βˆ’500 βˆ’ 150√10
π‘žπ‘™ = 𝑐1 𝑒(βˆ’500+150√10)𝑑
+ 𝑐2 𝑒(βˆ’500βˆ’150√10)𝑑
π‘ž π‘Ÿ = 𝐴0
π‘žβ€² π‘Ÿ = 0
π‘žβ€²β€² π‘Ÿ = 0
π‘žβ€²β€² + 1000π‘žβ€² + 25000π‘ž = 24
0 + 1000(0) + 25000(𝐴0) = 24
𝐴0 =
3
3125
, then
π‘ž π‘Ÿ =
3
3125
π‘ž = π‘žπ‘™ + π‘ž π‘Ÿ
π‘ž(𝑑) = 𝑐1 𝑒(βˆ’500+150√10)𝑑
+ 𝑐2 𝑒(βˆ’500βˆ’150√10)𝑑
+
3
3125
π‘ž(0) = 0
0 = 𝑐1 + 𝑐2 +
3
3125
𝑐1 + 𝑐2 = βˆ’
3
3125
...................................(1)
π‘žβ€²(𝑑) = (βˆ’500 + 150√10)𝑐1 𝑒(βˆ’500+150√10)𝑑
+ (βˆ’500 βˆ’ 150√10)𝑐2 𝑒(βˆ’500βˆ’150√10)𝑑
π‘žβ€²(0) = 0
0 = (βˆ’500 + 150√10)𝑐1 + (βˆ’500 βˆ’ 150√10)𝑐2 ........................... (2)
By using elimination method, we can find the value of c1 from (1) and (2).
(βˆ’500 βˆ’ 150√10)𝑐1 + (βˆ’500 βˆ’ 150√10)𝑐2 = βˆ’
3
3125
(βˆ’500 βˆ’ 150√10)
(βˆ’500 + 150√10)𝑐1 + (βˆ’500 βˆ’ 150√10)𝑐2 = 0
βˆ’300√10𝑐1 = βˆ’
3
3125
(βˆ’500 βˆ’ 150√10)
𝑐1 =
βˆ’5√10 βˆ’ 15
3125
By using (1), we can find the value of c2.
𝑐1 + 𝑐2 = βˆ’
3
3125
βˆ’5√10 βˆ’ 15
3125
+ 𝑐2 = βˆ’
3
3125
𝑐2 =
5√10 + 12
3125
After finding the value of c1 and c2, we get the equation.
π‘ž(𝑑) = (
βˆ’5√10 βˆ’ 15
3125
) 𝑒(βˆ’500+150√10)𝑑
+ (
5√10 + 12
3125
) 𝑒(βˆ’500βˆ’150√10)𝑑
+
3
3125
–
2. 𝑦′′ βˆ’ 4𝑦′ + 𝑦 = 2𝑑3
+ 3𝑑2
βˆ’ 1
Quadratic equation:
𝑑2
βˆ’ 4𝑑 + 1 = 0
𝑑1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
𝑑1,2 =
βˆ’(βˆ’4) Β± √(βˆ’4)2 βˆ’ 4(1)(1)
2(1)
𝑑1,2 =
4 ± √12
2
𝑑1,2 =
4 ± 2√3
2
𝑑1,2 = 2 Β± √3
𝑑1 = 2 + √3 and 𝑑2 = 2 βˆ’ √3
𝑦𝑙 = 𝑐1 𝑒(2+√3)𝑑
+ 𝑐2 𝑒(2βˆ’βˆš3)𝑑
π‘¦π‘Ÿ = 𝐴3 𝑑3
+ 𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0
𝑦′ π‘Ÿ = 3𝐴3 𝑑2
+ 2𝐴2 𝑑 + 𝐴1
𝑦′′ π‘Ÿ = 6𝐴3 𝑑 + 2𝐴2
𝑦′′ βˆ’ 4𝑦′ + 𝑦 = 2𝑑3
+ 3𝑑2
βˆ’ 1
(6𝐴3 𝑑 + 2𝐴2) βˆ’ 4(3𝐴3 𝑑2
+ 2𝐴2 𝑑 + 𝐴1) + (𝐴3 𝑑3
+ 𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0) = 2𝑑3
+ 3𝑑2
βˆ’ 1
𝐴3 𝑑3
+ (βˆ’12𝐴3 + 𝐴2)𝑑2
+ (6𝐴3 βˆ’ 8𝐴2 + 𝐴1)𝑑 + 𝐴1 + 𝐴0 = 2𝑑3
+ 3𝑑2
βˆ’ 1
Equation similarity:
𝐴3 = 2
βˆ’12𝐴3 + 𝐴2 = 3
βˆ’12(2) + 𝐴2 = 3
𝐴2 = 27
6𝐴3 βˆ’ 8𝐴2 + 𝐴1 = 0
6(2) βˆ’ 8(27) + 𝐴1 = 0
𝐴1 = 204
𝐴1 + 𝐴0 = βˆ’1
204 + 𝐴0 = βˆ’1
𝐴0 = βˆ’205
π‘¦π‘Ÿ = 2𝑑3
+ 27𝑑2
+ 204𝑑 βˆ’ 205
𝑦 = 𝑦𝑙 + π‘¦π‘Ÿ
𝑦(𝑑) = 𝑐1 𝑒(2+√3)𝑑
+ 𝑐2 𝑒(2βˆ’βˆš3)𝑑
+ 2𝑑3
+ 27𝑑2
+ 204𝑑 βˆ’ 205
𝑦(0) = 1
1 = 𝑐1 + 𝑐2 βˆ’ 205
𝑐1 + 𝑐2 = 206 .........................(1)
𝑦′(𝑑) = (2 + √3)𝑐1 𝑒(2+√3)𝑑
+ (2 βˆ’ √3)𝑐2 𝑒(2βˆ’βˆš3)𝑑
+ 6𝑑2
+ 54𝑑 + 204
𝑦′(0) = 1
1 = (2 + √3)𝑐1 + (2 βˆ’ √3)𝑐2 + 204
(2 + √3)𝑐1 + (2 βˆ’ √3)𝑐2 = βˆ’203 ........................... (2)
By using elimination and substitution method, the value of c1 and c2 can be obtained
from (1) and (2).
βˆ’203 = (2 + √3)𝑐1 + (2 βˆ’ √3)𝑐2........................... (2)
206 = (2 βˆ’ √3)𝑐1 + (2 βˆ’ √3)𝑐2 ...................................(1)
2√3𝑐1 = βˆ’203 βˆ’ 206(2 βˆ’ √3)
2√3𝑐1 = βˆ’715 + 206√3
𝑐1 =
βˆ’715√3 + 618
6
𝑐1 + 𝑐2 = 206
(
βˆ’715√3 + 618
6
) + 𝑐2 = 206
𝑐2 =
715√3 + 618
6
𝑦(𝑑) = (
βˆ’715√3+618
6
) 𝑒(2+√3)𝑑
+ (
715√3+618
6
) 𝑒(2βˆ’βˆš3)𝑑
+ 2𝑑3
+ 27𝑑2
+ 204𝑑 βˆ’ 205
–
TASK V (March 20th, 2014)
1.
𝑑2 π‘₯
𝑑𝑑2
+ 4
𝑑π‘₯
𝑑𝑑
+ 8π‘₯ = (20𝑑2
+ 16𝑑 βˆ’ 78)𝑒2𝑑
y(0)=y’(0)=0
2.
𝑑3 π‘ž
𝑑𝑑3 βˆ’ 5
𝑑2 π‘ž
𝑑𝑑2 + 25
π‘‘π‘ž
𝑑𝑑
βˆ’ 125π‘ž = (βˆ’500𝑑2
+ 465𝑑 βˆ’ 387)𝑒2𝑑
q(0)=q’(0)= q’’(0)=0
Solution:
1.
𝑑2 π‘₯
𝑑𝑑2
+ 4
𝑑π‘₯
𝑑𝑑
+ 8π‘₯ = (20𝑑2
+ 16𝑑 βˆ’ 78)𝑒2𝑑
y(0)=y’(0)=0
quadratic equation is
πœ†2
+ 4πœ† + 8 = 0
πœ†1,2 =
βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘
2π‘Ž
πœ†1,2 =
βˆ’4 Β± √42 βˆ’ 4(1)(8)
2(1)
πœ†1,2 =
βˆ’4 Β± βˆšβˆ’16
2
πœ†1,2 = βˆ’2 Β± 2𝑖
𝑦𝑙 = π‘’βˆ’2𝑑
(𝑐1 cos 2𝑑 + 𝑐2 sin 2𝑑)
π‘¦π‘Ÿ = (𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)𝑒2𝑑
𝑦′ π‘Ÿ = (2𝐴2 𝑑 + 𝐴1)𝑒2𝑑
+ (𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)(2𝑒2𝑑)
𝑦′′ π‘Ÿ = 2𝐴2 𝑒2𝑑
+ (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)(4𝑒2𝑑)
𝑦′′
+ 4𝑦′ + 8𝑦 = (20𝑑2
+ 16𝑑 βˆ’ 78)𝑒2𝑑
2𝐴2 𝑒2𝑑
+ (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)(4𝑒2𝑑) +
4{(2𝐴2 𝑑 + 𝐴1)𝑒2𝑑
+ (𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)(2𝑒2𝑑)} + 8{(𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)𝑒2𝑑} = (20𝑑2
+
16𝑑 βˆ’ 78)𝑒2𝑑
(2𝐴2 + 8𝐴1 + 20𝐴0)𝑒2𝑑
+ (16𝐴2 + 20𝐴1)𝑑𝑒2𝑑
+ (20𝐴2)𝑑2
𝑒2𝑑
= (20𝑑2
+ 16𝑑 βˆ’
78)𝑒2𝑑
ο‚· 20𝐴2 = 20
𝐴2 = 1
ο‚· 16𝐴2 + 20𝐴1 = 16
16(1) + 20𝐴1 = 16
20𝐴1 = 0
𝐴1 = 0
ο‚· 2𝐴2 + 8𝐴1 + 20𝐴0 = βˆ’78
2(1) + 8(0) + 20𝐴0 = βˆ’78
20𝐴0 = βˆ’78 βˆ’ 2
20𝐴0 = βˆ’80
𝐴0 = βˆ’4
π‘¦π‘Ÿ = (𝑑2
βˆ’ 4)𝑒2𝑑
y = yl + yr
𝑦(𝑑) = π‘’βˆ’2𝑑(𝑐1 cos 2𝑑 + 𝑐2 sin 2𝑑) + (𝑑2
βˆ’ 4)𝑒2𝑑
𝑦′(𝑑)
= (βˆ’2π‘’βˆ’2𝑑)(𝑐1 cos 2𝑑 + 𝑐2 sin 2𝑑) + π‘’βˆ’2𝑑(βˆ’2𝑐1 sin 2𝑑 + 2𝑐2 cos 2𝑑) + 2𝑑𝑒2𝑑
+
(𝑑2
βˆ’ 4)(2𝑒2𝑑)
𝑦(0) = 0
0 = 𝑐1 βˆ’ 4
𝑐1 = 4
𝑦′(0) = 0
0 = βˆ’2𝑐1 + 2𝑐2 βˆ’ 8
8 = βˆ’2(4) + 2𝑐2
𝑐2 = 8
𝑦(𝑑) = π‘’βˆ’2𝑑(4 cos 2𝑑 + 8 sin 2𝑑) + (𝑑2
βˆ’ 4)𝑒2𝑑
2.
𝑑3 π‘ž
𝑑𝑑3
βˆ’ 5
𝑑2 π‘ž
𝑑𝑑2
+ 25
π‘‘π‘ž
𝑑𝑑
βˆ’ 125π‘ž = (βˆ’500𝑑2
+ 465𝑑 βˆ’ 387)𝑒2𝑑
q(0)=q’(0)= q’’(0)=0
Quadratic equation is:
πœ†3
βˆ’ 5πœ†2
+ 25πœ† βˆ’ 125 = 0
πœ†1 = 5
πœ†2 = 5𝑖
πœ†3 = βˆ’5𝑖
𝑦𝑙 = 𝑐1 𝑒5𝑑
+ 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑
π‘¦π‘Ÿ = (𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)𝑒2𝑑
𝑦′
π‘Ÿ
= (2𝐴2 𝑑 + 𝐴1)𝑒2𝑑
+ (𝐴2 𝑑2
+ 𝐴1 𝑑 + 𝐴0)(2𝑒2𝑑
)
= 2𝐴2 𝑑𝑒2𝑑
+ 𝐴1 𝑒2𝑑
+ 2𝐴2 𝑑2
𝑒2𝑑
+ 2𝐴1 𝑑𝑒2𝑑
+ 2𝐴0 𝑒2𝑑
𝑦′′
π‘Ÿ
= 2𝐴2 𝑒2𝑑
+ 8𝐴2 𝑑𝑒2𝑑
+ 2𝐴1 𝑒2𝑑
+ 4𝐴2 𝑑𝑒2𝑑
+ 4𝐴2 𝑑2
𝑒2𝑑
+ 2𝐴1 𝑒2𝑑
+ 4𝐴1 𝑑𝑒2𝑑
+
4𝐴0 𝑒2𝑑
𝑦′′′
π‘Ÿ
= 12𝐴2 𝑒2𝑑
+ 12𝐴1 𝑒2𝑑
+ 8𝐴0 𝑒2𝑑
+ 24𝐴2 𝑑𝑒2𝑑
+ 8𝐴1 𝑑𝑒2𝑑
+ 8𝐴2 𝑑2
𝑒2𝑑
𝑦′′′
βˆ’ 5𝑦′′
+ 25𝑦′ βˆ’ 125𝑦 = (βˆ’500𝑑2
+ 465𝑑 βˆ’ 387)𝑒2𝑑
12𝐴2 𝑒2𝑑
+ 12𝐴1 𝑒2𝑑
+ 8𝐴0 𝑒2𝑑
+ 24𝐴2 𝑑𝑒2𝑑
+ 8𝐴1 𝑑𝑒2𝑑
+ 8𝐴2 𝑑2
𝑒2𝑑
βˆ’ 5{2𝐴2 𝑒2𝑑
+
8𝐴2 𝑑𝑒2𝑑
+ 2𝐴1 𝑒2𝑑
+ 4𝐴2 𝑑𝑒2𝑑
+ 4𝐴2 𝑑2
𝑒2𝑑
+ 2𝐴1 𝑒2𝑑
+ 4𝐴1 𝑑𝑒2𝑑
+ 4𝐴0 𝑒2𝑑 } +
25{2𝐴2 𝑑𝑒2𝑑
+ 𝐴1 𝑒2𝑑
+ 2𝐴2 𝑑2
𝑒2𝑑
+ 2𝐴1 𝑑𝑒2𝑑
+ 2𝐴0 𝑒2𝑑} βˆ’ 125{(𝐴2 𝑑2
+ 𝐴1 𝑑 +
𝐴0)𝑒2𝑑} = (βˆ’500𝑑2
+ 465𝑑 βˆ’ 387)𝑒2𝑑
(2𝐴2 + 17𝐴1 βˆ’ 87𝐴0)𝑒2𝑑
+ (34𝐴2 βˆ’ 87𝐴1)𝑑𝑒2𝑑
+ (βˆ’87𝐴2)𝑑2
𝑒2𝑑
= βˆ’500𝑑2
𝑒2𝑑
+
465𝑑𝑒2𝑑
βˆ’ 387𝑒2𝑑
ο‚· βˆ’87𝐴2 = βˆ’500
𝐴2 =
500
87
ο‚· 34𝐴2 βˆ’ 87𝐴1 = 465
34 (
500
87
) βˆ’ 87𝐴1 = 465
𝐴1 =
βˆ’23455
7569
ο‚· 2𝐴2 + 17𝐴1 βˆ’ 87𝐴0 = βˆ’387
2 (
500
87
) + 17 (
βˆ’23455
7569
) βˆ’ 87𝐴0 = βˆ’387
𝐴0 =
2617468
658503
π‘¦π‘Ÿ = (
500
87
𝑑2
βˆ’
23455
7569
𝑑 +
2617468
658503
) 𝑒2𝑑
𝑦 = 𝑦𝑙 + π‘¦π‘Ÿ
𝑦(𝑑) = 𝑐1 𝑒5𝑑
+ 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑 + (
500
87
𝑑2
βˆ’
23455
7569
𝑑 +
2617468
658503
) 𝑒2𝑑
𝑦′
(𝑑) = 5𝑐1 𝑒5𝑑
βˆ’ 5𝑐2 sin 5𝑑 + 5𝑐3 cos 5𝑑 + (
1000
87
𝑑 βˆ’
23455
7569
) 𝑒2𝑑
+ (
500
87
𝑑2
βˆ’
23455
7569
𝑑 +
2617468
658503
) (2𝑒2𝑑)
𝑦′′(𝑑) = 25𝑐1 𝑒5𝑑
βˆ’ 25𝑐2 cos5𝑑 βˆ’ 25𝑐3 sin5𝑑 +
1000
87
𝑒2𝑑
+ (
1000
87
𝑑 βˆ’
23455
7569
) (2𝑒2𝑑) +
(
1000
87
𝑑 βˆ’
23455
7569
) (2𝑒2𝑑) + (
500
87
𝑑2
βˆ’
23455
7569
𝑑 +
2617468
658503
) (4𝑒2𝑑)
𝑦(0) = 0
0 = 𝑐1 + 𝑐2 +
2617468
658503
𝑐1 + 𝑐2 = βˆ’
2617468
658503
................................... (1)
𝑦′(0) = 0
0 = 5𝑐1 + 5𝑐3 βˆ’
23455
7569
+
5234936
658503
5𝑐1 + 5𝑐3 = βˆ’
3194351
658503
𝑐1 + 𝑐3 = βˆ’
3194351
3292515
.................................... (2)
𝑦′′(0) = 0
0 = 25𝑐1 βˆ’ 25𝑐2 +
1000
87
βˆ’
46910
7569
βˆ’
46910
7569
+
10469872
658503
25𝑐1 βˆ’ 25𝑐2 = βˆ’
9876532
658503
.................................... (3)
25𝑐1 + 25𝑐2 = βˆ’
65436700
658503
................................... (1)
50𝑐1 = βˆ’
75313232
658503
𝑐1 = βˆ’
75313232
32925150
+
From equation (1), we get the value of c2.
𝑐2 = βˆ’
2617468
658503
+
75313232
32925150
𝑐2 = βˆ’
55560168
32925150
From equation (2), we get the value of c3.
𝑐3 = βˆ’
3194351
3292515
+
75313232
32925150
𝑐3 =
43369722
32925150
𝑦(𝑑) = βˆ’
75313232
32925150
𝑒5𝑑
βˆ’
55560168
32925150
cos 5𝑑 +
43369722
32925150
sin 5𝑑 + (
500
87
𝑑2
βˆ’
23455
7569
𝑑 +
2617468
658503
) 𝑒2𝑑

Weitere Γ€hnliche Inhalte

Was ist angesagt?

Exponent & Logarithm
Exponent &  LogarithmExponent &  Logarithm
Exponent & Logarithm
guest0ffcb4
Β 
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ΰΈ΄ΰΈŸΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
Yodhathai Reesrikom
Β 
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ΰΈ΄ΰΈŸΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
Yodhathai Reesrikom
Β 

Was ist angesagt? (14)

Exponent & Logarithm
Exponent &  LogarithmExponent &  Logarithm
Exponent & Logarithm
Β 
Tugas blog-matematika
Tugas blog-matematikaTugas blog-matematika
Tugas blog-matematika
Β 
Ejemplos matriz inversa
Ejemplos matriz inversaEjemplos matriz inversa
Ejemplos matriz inversa
Β 
31350052 introductory-mathematical-analysis-textbook-solution-manual
31350052 introductory-mathematical-analysis-textbook-solution-manual31350052 introductory-mathematical-analysis-textbook-solution-manual
31350052 introductory-mathematical-analysis-textbook-solution-manual
Β 
Solutions manual for fundamentals of business math canadian 3rd edition by je...
Solutions manual for fundamentals of business math canadian 3rd edition by je...Solutions manual for fundamentals of business math canadian 3rd edition by je...
Solutions manual for fundamentals of business math canadian 3rd edition by je...
Β 
solucionario de purcell 3
solucionario de purcell 3solucionario de purcell 3
solucionario de purcell 3
Β 
solucionario de purcell 2
solucionario de purcell 2solucionario de purcell 2
solucionario de purcell 2
Β 
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ΰΈ΄ΰΈŸΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈ„ΰΈ£ΰΈ±ΰΈšΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
Β 
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ΰΈ΄ΰΈŸΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
ΰΈ£ΰΈ§ΰΈ‘ΰΉƒΰΈšΰΈ‡ΰΈ²ΰΈ™ΰΈˆΰΉ‰ΰΈ²ΰΈ₯ΰΈΉΰΈΰΈ¨ΰΈ΄ΰΈ©ΰΈ’ΰΉŒΰΉ€ΰΈ₯ิฟ
Β 
Trabajo matemΓ‘ticas 7
Trabajo matemΓ‘ticas 7Trabajo matemΓ‘ticas 7
Trabajo matemΓ‘ticas 7
Β 
Homework packet
Homework packetHomework packet
Homework packet
Β 
solucionario de purcell 0
solucionario de purcell 0solucionario de purcell 0
solucionario de purcell 0
Β 
V2.0
V2.0V2.0
V2.0
Β 
Capitulo 7 Soluciones Purcell 9na Edicion
Capitulo 7 Soluciones Purcell 9na EdicionCapitulo 7 Soluciones Purcell 9na Edicion
Capitulo 7 Soluciones Purcell 9na Edicion
Β 

Andere mochten auch

The colors of the flag
The colors of the flagThe colors of the flag
The colors of the flag
forever97
Β 
Power point essentials #15 8Β°b
Power point essentials #15 8Β°bPower point essentials #15 8Β°b
Power point essentials #15 8Β°b
forever97
Β 
Final photos
Final photosFinal photos
Final photos
sholawelch
Β 
Informatica
InformaticaInformatica
Informatica
Miquel2897
Β 
Jaguar
JaguarJaguar
Jaguar
leerling5
Β 
ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для рСсторанов
ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для Ρ€Π΅ΡΡ‚ΠΎΡ€Π°Π½ΠΎΠ²ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для рСсторанов
ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для рСсторанов
SoGe Mobile
Β 

Andere mochten auch (19)

Numerical Solutions to Ordinary Differential Equations in Scilab
Numerical Solutions to Ordinary Differential Equations in ScilabNumerical Solutions to Ordinary Differential Equations in Scilab
Numerical Solutions to Ordinary Differential Equations in Scilab
Β 
The colors of the flag
The colors of the flagThe colors of the flag
The colors of the flag
Β 
Power point essentials #15 8Β°b
Power point essentials #15 8Β°bPower point essentials #15 8Β°b
Power point essentials #15 8Β°b
Β 
Missing andy β€˜kings for the weekend’
Missing andy β€˜kings for the weekend’Missing andy β€˜kings for the weekend’
Missing andy β€˜kings for the weekend’
Β 
Final photos
Final photosFinal photos
Final photos
Β 
AdSense Ban & Earning Boost-Up & Your Responsibilities
AdSense Ban & Earning Boost-Up & Your ResponsibilitiesAdSense Ban & Earning Boost-Up & Your Responsibilities
AdSense Ban & Earning Boost-Up & Your Responsibilities
Β 
Software Cost Estimation
Software Cost EstimationSoftware Cost Estimation
Software Cost Estimation
Β 
Fotosintesis
FotosintesisFotosintesis
Fotosintesis
Β 
MR STUCHBERY'S TOP FIVE TEXT ANALYSIS TIPS.
MR STUCHBERY'S TOP FIVE TEXT ANALYSIS TIPS.MR STUCHBERY'S TOP FIVE TEXT ANALYSIS TIPS.
MR STUCHBERY'S TOP FIVE TEXT ANALYSIS TIPS.
Β 
Maruki
MarukiMaruki
Maruki
Β 
Informatica
InformaticaInformatica
Informatica
Β 
Smart analyzer v9 product profile
Smart analyzer v9 product profileSmart analyzer v9 product profile
Smart analyzer v9 product profile
Β 
Disney
DisneyDisney
Disney
Β 
save water and our planet "EARTH"....
save water and our planet "EARTH"....save water and our planet "EARTH"....
save water and our planet "EARTH"....
Β 
Nooges Brochure
Nooges BrochureNooges Brochure
Nooges Brochure
Β 
Illinois supreme court decision in re pension reform litigation - May 8, 2015
Illinois supreme court decision in re pension reform litigation - May 8, 2015Illinois supreme court decision in re pension reform litigation - May 8, 2015
Illinois supreme court decision in re pension reform litigation - May 8, 2015
Β 
Jaguar
JaguarJaguar
Jaguar
Β 
ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для рСсторанов
ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для Ρ€Π΅ΡΡ‚ΠΎΡ€Π°Π½ΠΎΠ²ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для рСсторанов
ΠœΠΎΠ±ΠΈΠ»ΡŒΠ½Ρ‹Π΅ прилоТСния для рСсторанов
Β 
La mia casa Γ¨ la tua casa
La mia casa Γ¨ la tua casaLa mia casa Γ¨ la tua casa
La mia casa Γ¨ la tua casa
Β 

Γ„hnlich wie Task compilation - Differential Equation II

Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)
Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)
Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)
Nurkhalifah Anwar
Β 

Γ„hnlich wie Task compilation - Differential Equation II (20)

SUEC 高中 Adv Maths (Locus) (Part 1).pptx
SUEC 高中 Adv Maths (Locus) (Part 1).pptxSUEC 高中 Adv Maths (Locus) (Part 1).pptx
SUEC 高中 Adv Maths (Locus) (Part 1).pptx
Β 
Calculo
CalculoCalculo
Calculo
Β 
Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)
Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)
Tugas 5.6 kalkulus aplikasi integral tentu (luas bidang datar)
Β 
Maths-MS_Term2 (1).pdf
Maths-MS_Term2 (1).pdfMaths-MS_Term2 (1).pdf
Maths-MS_Term2 (1).pdf
Β 
SUEC 高中 Adv Maths (Locus) (Part 2).pptx
SUEC 高中 Adv Maths (Locus) (Part 2).pptxSUEC 高中 Adv Maths (Locus) (Part 2).pptx
SUEC 高中 Adv Maths (Locus) (Part 2).pptx
Β 
SUEC 高中 Adv Maths (AP).pptx
SUEC 高中 Adv Maths (AP).pptxSUEC 高中 Adv Maths (AP).pptx
SUEC 高中 Adv Maths (AP).pptx
Β 
Question and Solutions Exponential.pdf
Question and Solutions Exponential.pdfQuestion and Solutions Exponential.pdf
Question and Solutions Exponential.pdf
Β 
Latihan 8.3 Thomas (Kalkulus Integral)
Latihan 8.3 Thomas (Kalkulus Integral)Latihan 8.3 Thomas (Kalkulus Integral)
Latihan 8.3 Thomas (Kalkulus Integral)
Β 
Ejercicios resueltos de analisis matematico 1
Ejercicios resueltos de analisis matematico 1Ejercicios resueltos de analisis matematico 1
Ejercicios resueltos de analisis matematico 1
Β 
Study Material Numerical Solution of Odinary Differential Equations
Study Material Numerical Solution of Odinary Differential EquationsStudy Material Numerical Solution of Odinary Differential Equations
Study Material Numerical Solution of Odinary Differential Equations
Β 
INVERSE DIFFERENTIAL OPERATOR
INVERSE DIFFERENTIAL OPERATORINVERSE DIFFERENTIAL OPERATOR
INVERSE DIFFERENTIAL OPERATOR
Β 
Ernest f. haeussler, richard s. paul y richard j. wood. matemΓ‘ticas para admi...
Ernest f. haeussler, richard s. paul y richard j. wood. matemΓ‘ticas para admi...Ernest f. haeussler, richard s. paul y richard j. wood. matemΓ‘ticas para admi...
Ernest f. haeussler, richard s. paul y richard j. wood. matemΓ‘ticas para admi...
Β 
Solucionario de matemΓ‘ticas para administaciΓ³n y economia
Solucionario de matemΓ‘ticas para administaciΓ³n y economiaSolucionario de matemΓ‘ticas para administaciΓ³n y economia
Solucionario de matemΓ‘ticas para administaciΓ³n y economia
Β 
Luas daerah bidang datar (kalkulus integral)
Luas daerah bidang datar (kalkulus integral) Luas daerah bidang datar (kalkulus integral)
Luas daerah bidang datar (kalkulus integral)
Β 
taller transformaciones lineales
taller transformaciones linealestaller transformaciones lineales
taller transformaciones lineales
Β 
Calculus revision card
Calculus  revision cardCalculus  revision card
Calculus revision card
Β 
Calculus revision card
Calculus  revision cardCalculus  revision card
Calculus revision card
Β 
Taller 1 parcial 3
Taller 1 parcial 3Taller 1 parcial 3
Taller 1 parcial 3
Β 
Factoring common monomial
Factoring common monomialFactoring common monomial
Factoring common monomial
Β 
Fismat chapter 4
Fismat chapter 4Fismat chapter 4
Fismat chapter 4
Β 

Mehr von Jazz Michele Pasaribu (8)

Lesson plan of experimental and control class
Lesson plan of experimental and control classLesson plan of experimental and control class
Lesson plan of experimental and control class
Β 
Bisection and fixed point method
Bisection and fixed point methodBisection and fixed point method
Bisection and fixed point method
Β 
RPP Suku Banyak
RPP Suku BanyakRPP Suku Banyak
RPP Suku Banyak
Β 
Creating learning environment
Creating learning environmentCreating learning environment
Creating learning environment
Β 
Creating Learning Environment
Creating Learning EnvironmentCreating Learning Environment
Creating Learning Environment
Β 
Professionalism in Education
Professionalism in EducationProfessionalism in Education
Professionalism in Education
Β 
Representation
RepresentationRepresentation
Representation
Β 
Realism philosophy
Realism philosophyRealism philosophy
Realism philosophy
Β 

KΓΌrzlich hochgeladen

An Overview of Mutual Funds Bcom Project.pdf
An Overview of Mutual Funds Bcom Project.pdfAn Overview of Mutual Funds Bcom Project.pdf
An Overview of Mutual Funds Bcom Project.pdf
SanaAli374401
Β 
Beyond the EU: DORA and NIS 2 Directive's Global Impact
Beyond the EU: DORA and NIS 2 Directive's Global ImpactBeyond the EU: DORA and NIS 2 Directive's Global Impact
Beyond the EU: DORA and NIS 2 Directive's Global Impact
PECB
Β 
Seal of Good Local Governance (SGLG) 2024Final.pptx
Seal of Good Local Governance (SGLG) 2024Final.pptxSeal of Good Local Governance (SGLG) 2024Final.pptx
Seal of Good Local Governance (SGLG) 2024Final.pptx
negromaestrong
Β 

KΓΌrzlich hochgeladen (20)

microwave assisted reaction. General introduction
microwave assisted reaction. General introductionmicrowave assisted reaction. General introduction
microwave assisted reaction. General introduction
Β 
psychiatric nursing HISTORY COLLECTION .docx
psychiatric  nursing HISTORY  COLLECTION  .docxpsychiatric  nursing HISTORY  COLLECTION  .docx
psychiatric nursing HISTORY COLLECTION .docx
Β 
Unit-IV; Professional Sales Representative (PSR).pptx
Unit-IV; Professional Sales Representative (PSR).pptxUnit-IV; Professional Sales Representative (PSR).pptx
Unit-IV; Professional Sales Representative (PSR).pptx
Β 
Unit-IV- Pharma. Marketing Channels.pptx
Unit-IV- Pharma. Marketing Channels.pptxUnit-IV- Pharma. Marketing Channels.pptx
Unit-IV- Pharma. Marketing Channels.pptx
Β 
Advanced Views - Calendar View in Odoo 17
Advanced Views - Calendar View in Odoo 17Advanced Views - Calendar View in Odoo 17
Advanced Views - Calendar View in Odoo 17
Β 
An Overview of Mutual Funds Bcom Project.pdf
An Overview of Mutual Funds Bcom Project.pdfAn Overview of Mutual Funds Bcom Project.pdf
An Overview of Mutual Funds Bcom Project.pdf
Β 
Mehran University Newsletter Vol-X, Issue-I, 2024
Mehran University Newsletter Vol-X, Issue-I, 2024Mehran University Newsletter Vol-X, Issue-I, 2024
Mehran University Newsletter Vol-X, Issue-I, 2024
Β 
SOCIAL AND HISTORICAL CONTEXT - LFTVD.pptx
SOCIAL AND HISTORICAL CONTEXT - LFTVD.pptxSOCIAL AND HISTORICAL CONTEXT - LFTVD.pptx
SOCIAL AND HISTORICAL CONTEXT - LFTVD.pptx
Β 
Beyond the EU: DORA and NIS 2 Directive's Global Impact
Beyond the EU: DORA and NIS 2 Directive's Global ImpactBeyond the EU: DORA and NIS 2 Directive's Global Impact
Beyond the EU: DORA and NIS 2 Directive's Global Impact
Β 
Mattingly "AI & Prompt Design: Structured Data, Assistants, & RAG"
Mattingly "AI & Prompt Design: Structured Data, Assistants, & RAG"Mattingly "AI & Prompt Design: Structured Data, Assistants, & RAG"
Mattingly "AI & Prompt Design: Structured Data, Assistants, & RAG"
Β 
Accessible design: Minimum effort, maximum impact
Accessible design: Minimum effort, maximum impactAccessible design: Minimum effort, maximum impact
Accessible design: Minimum effort, maximum impact
Β 
Unit-V; Pricing (Pharma Marketing Management).pptx
Unit-V; Pricing (Pharma Marketing Management).pptxUnit-V; Pricing (Pharma Marketing Management).pptx
Unit-V; Pricing (Pharma Marketing Management).pptx
Β 
CΓ³digo Creativo y Arte de Software | Unidad 1
CΓ³digo Creativo y Arte de Software | Unidad 1CΓ³digo Creativo y Arte de Software | Unidad 1
CΓ³digo Creativo y Arte de Software | Unidad 1
Β 
Seal of Good Local Governance (SGLG) 2024Final.pptx
Seal of Good Local Governance (SGLG) 2024Final.pptxSeal of Good Local Governance (SGLG) 2024Final.pptx
Seal of Good Local Governance (SGLG) 2024Final.pptx
Β 
Mixin Classes in Odoo 17 How to Extend Models Using Mixin Classes
Mixin Classes in Odoo 17  How to Extend Models Using Mixin ClassesMixin Classes in Odoo 17  How to Extend Models Using Mixin Classes
Mixin Classes in Odoo 17 How to Extend Models Using Mixin Classes
Β 
Measures of Central Tendency: Mean, Median and Mode
Measures of Central Tendency: Mean, Median and ModeMeasures of Central Tendency: Mean, Median and Mode
Measures of Central Tendency: Mean, Median and Mode
Β 
Nutritional Needs Presentation - HLTH 104
Nutritional Needs Presentation - HLTH 104Nutritional Needs Presentation - HLTH 104
Nutritional Needs Presentation - HLTH 104
Β 
Web & Social Media Analytics Previous Year Question Paper.pdf
Web & Social Media Analytics Previous Year Question Paper.pdfWeb & Social Media Analytics Previous Year Question Paper.pdf
Web & Social Media Analytics Previous Year Question Paper.pdf
Β 
Presentation by Andreas Schleicher Tackling the School Absenteeism Crisis 30 ...
Presentation by Andreas Schleicher Tackling the School Absenteeism Crisis 30 ...Presentation by Andreas Schleicher Tackling the School Absenteeism Crisis 30 ...
Presentation by Andreas Schleicher Tackling the School Absenteeism Crisis 30 ...
Β 
APM Welcome, APM North West Network Conference, Synergies Across Sectors
APM Welcome, APM North West Network Conference, Synergies Across SectorsAPM Welcome, APM North West Network Conference, Synergies Across Sectors
APM Welcome, APM North West Network Conference, Synergies Across Sectors
Β 

Task compilation - Differential Equation II

  • 1. DIFFERENTIAL EQUATION II TASK COMPILATION 3/27/2014 MARIA PRISCILLYA PASARIBU IDN. 4103312018
  • 2. TASK I (February, 13th 2014) Determine the solution of:: 1. 𝑑2 𝑦 𝑑𝑑2 βˆ’ 2 𝑑𝑦 𝑑𝑑 βˆ’ 5𝑦 = 0, y(0)=0; y’(0)=1 2. 𝑑2 𝑦 𝑑𝑑2 βˆ’ 3 𝑑𝑦 𝑑𝑑 = 0, y(0)=0; y’(0)=1 3. 𝑑2 𝑦 𝑑𝑑2 βˆ’ 4 𝑑𝑦 𝑑𝑑 βˆ’ 4𝑦 = 0, y(0)=0; y’(0)=1 Solution: 1. 𝑑2 𝑦 𝑑𝑑2 βˆ’ 2 𝑑𝑦 𝑑𝑑 βˆ’ 5𝑦 = 0, y(0)=0; y’(0)=1 Characteristic Equation: πœ†2 βˆ’ 2πœ† βˆ’ 5 = 0 πœ†1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž = βˆ’(βˆ’2) Β± √(βˆ’2)2 βˆ’ 4(1)(βˆ’5) 2(1) = 2 Β± √4 + 20 2 = 2 Β± √24 2 = 2 Β± 2√6 2 = 1 Β± √6 πœ†1and πœ†2 are real and distinct, then 𝑦 = 𝑐1 𝑒 π‘š1 π‘₯ + 𝑐2 𝑒 π‘š2 π‘₯ 𝑦(0) = 0 0 = 𝑐1 + 𝑐2 𝑐1 = βˆ’π‘2 .................... (1) 𝑦′(0) = 1 𝑦′(π‘₯) = (1 + √6)𝑐1 𝑒(1+√6)π‘₯ + (1 βˆ’ √6)𝑐1 𝑒(1βˆ’βˆš6)π‘₯ 1 = (1 + √6)𝑐1 + (1 βˆ’ √6)𝑐2 1 = (1 + √6)𝑐1 + (1 βˆ’ √6)(βˆ’π‘1) 1 = 𝑐1(1 + √6 βˆ’ 1 + √6) 1 = 2√6𝑐1 𝑐1 = 1 12 √6
  • 3. 𝑐1 = βˆ’π‘2 .................... (1) 𝑐2 = βˆ’ 1 12 √6 Maka, 𝑦 = 1 12 √6𝑒(1+√6)π‘₯ βˆ’ 1 12 √6𝑒(1βˆ’βˆš6)π‘₯ 2. 𝑑2 𝑦 𝑑𝑑2 βˆ’ 3 𝑑𝑦 𝑑𝑑 = 0, y(0)=0; y’(0)=1 Characteristic Equation:πœ†2 βˆ’ 3πœ† = 0 πœ†(πœ† βˆ’ 3) = 0 πœ†1 = 0 ∨ πœ†2 = 3 πœ†1and πœ†2 are real and distinct, then 𝑦 = 𝑐1 𝑒 π‘š1 π‘₯ + 𝑐2 𝑒 π‘š2 π‘₯ 𝑦 = 𝑐1 𝑒0π‘₯ + 𝑐2 𝑒3π‘₯ 𝑦(0) = 0 0 = 𝑐1 + 𝑐2 𝑐1 = βˆ’π‘2 .................... (1) 𝑦′(0) = 1 𝑦′(π‘₯) = 3𝑐2 3π‘₯ 1 = 3𝑐2 𝑐2 = 1 3 𝑐1 = βˆ’ 1 3 Then, 𝑦 = βˆ’ 1 3 𝑒 π‘š1 π‘₯ + 1 3 𝑒 π‘š2 π‘₯ 3. 𝑑2 𝑦 𝑑𝑑2 βˆ’ 4 𝑑𝑦 𝑑𝑑 βˆ’ 4𝑦 = 0, y(0)=0; y’(0)=1 Characteristic Equation:πœ†2 βˆ’ 4πœ† βˆ’ 4 = 0 πœ†1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž = βˆ’(βˆ’4) Β± √(βˆ’4)2 βˆ’ 4(1)(βˆ’4) 2(1) = 4 Β± √16 + 16 2 = 4 Β± 4√2 2 = 2 Β± 2√2
  • 4. πœ†1and πœ†2 are real and distinct, then 𝑦 = 𝑐1 𝑒 π‘š1 π‘₯ + 𝑐2 𝑒 π‘š2 π‘₯ 𝑦 = 𝑐1 𝑒(2+2√2)π‘₯ + 𝑐2 𝑒(2βˆ’2√2)π‘₯ 𝑦(0) = 0 0 = 𝑐1 + 𝑐2 𝑐1 = βˆ’π‘2 .................... (1) 𝑦′(0) = 1 𝑦′(π‘₯) = (2 + 2√2)𝑐1 𝑒(2+2√2)π‘₯ + (2 βˆ’ 2√2)𝑐2 𝑒(2βˆ’2√2)π‘₯ 1 = (2 + 2√2)𝑐1 + (2 βˆ’ 2√2)𝑐2 1 = (2 + 2√2)𝑐1 + (2 βˆ’ 2√2)(βˆ’π‘1) 1 = 𝑐1(2 + 2√2 βˆ’ 2 + 2√2) 1 = 𝑐1(4√2) 𝑐1 = 1 8 √2 𝑐1 = βˆ’π‘2 .................... (1) 𝑐2 = βˆ’ 1 8 √2 Maka, 𝑦 = 1 8 √2𝑒(2+2√2)π‘₯ βˆ’ 1 8 √2𝑒(2βˆ’2√2)π‘₯
  • 5. TASK II (February, 20th 2014) Solve these equation: 1. 𝑑4 𝑦 𝑑π‘₯4 + 10 𝑑2 𝑦 𝑑π‘₯2 + 9𝑦 = 0 2. 𝑑4 𝑦 𝑑π‘₯4 + 𝑑3 𝑦 𝑑π‘₯3 + 𝑑2 𝑦 𝑑π‘₯2 + 2𝑦 = 0 3. 𝑦′′′ + 4𝑦′ = 0 4. 𝑦(4) + 4𝑦′′ βˆ’ 𝑦′ + 6𝑦 = 0 5. 𝑑6 𝑦 𝑑π‘₯6 βˆ’ 4 𝑑5 𝑦 𝑑π‘₯5 + 16 𝑑4 𝑦 𝑑π‘₯4 βˆ’ 12 𝑑3 𝑦 𝑑π‘₯3 + 41 𝑑2 𝑦 𝑑π‘₯2 βˆ’ 8 𝑑𝑦 𝑑π‘₯ + 26𝑦 = 0 Solution: 1. 𝑑4 𝑦 𝑑π‘₯4 + 10 𝑑2 𝑦 𝑑π‘₯2 + 9𝑦 = 0 Characteristic equation: πœ†4 + 10πœ†2 + 9 = 0 (πœ†2 + 9)(πœ†2 + 1) = 0 (πœ† + 3𝑖)(πœ† βˆ’ 3𝑖)(πœ† + 𝑖)(πœ† βˆ’ 𝑖) = 0 πœ†1 = βˆ’3𝑖 ⋁ πœ†2 = βˆ’3𝑖 ⋁ πœ†3 = βˆ’π‘– ⋁ πœ†3 = 𝑖 So, the solution is 𝑦 = 𝐢1 cos 3π‘₯ + 𝐢2 sin 3π‘₯ + 𝐢3 cos π‘₯ + 𝐢4 sin π‘₯ 2. 𝑑4 𝑦 𝑑π‘₯4 + 𝑑3 𝑦 𝑑π‘₯3 + 𝑑2 𝑦 𝑑π‘₯2 + 2𝑦 = 0 Characteristic equation: πœ†4 + πœ†3 + πœ†2 + 2 = 0 (πœ†2 βˆ’ πœ† + 1)(πœ†2 + 2πœ† + 2) = 0 ο‚· (πœ†2 βˆ’ πœ† + 1) = 0 πœ†1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž πœ†1,2 = βˆ’(βˆ’1) Β± √(βˆ’1)2 βˆ’ 4(1)(1) 2(1) πœ†1,2 = 1 Β± √1 βˆ’ 4 2 πœ†1,2 = 1 Β± √3𝑖 2 πœ†1 = 1 2 + 1 2 √3𝑖 and πœ†2 = 1 2 βˆ’ 1 2 √3𝑖 ο‚· (πœ†2 + 2πœ† + 2) = 0 πœ†3,4 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž
  • 6. πœ†3,4 = βˆ’(2) Β± √(2)2 βˆ’ 4(1)(2) 2(1) πœ†3,4 = βˆ’2 Β± √4 βˆ’ 8 2 πœ†3,4 = βˆ’2 Β± 2𝑖 2 πœ†3 = βˆ’1 + 𝑖 and πœ†4 = βˆ’1 βˆ’ 𝑖 So, the solution is 𝑦 = 𝑒 1 2 π‘₯ (𝐢1 cos 1 2 √3π‘₯ + 𝐢2 sin 1 2 √3π‘₯) + π‘’βˆ’π‘₯ (𝐢3 cos π‘₯ + 𝐢4 sin π‘₯) 3. 𝑦′′′ + 4𝑦′ = 0 Characteristic equation: πœ†3 + 4πœ† = 0 πœ†(πœ†2 + 4) = 0 πœ†(πœ† + 2𝑖)(πœ† βˆ’ 2𝑖) = 0 πœ†1 = 0 ⋁ πœ†2 = βˆ’2𝑖 ⋁ πœ†3 = 2𝑖 So, the solution is 𝑦 = 𝐢1 + 𝐢2cos2π‘₯ + 𝐢3 sin 2π‘₯ 4. 𝑦(4) + 4𝑦′′ βˆ’ 𝑦′ + 6𝑦 = 0 Characteristics equation is πœ†4 + 4πœ†2 βˆ’ πœ† + 6 = 0 (πœ†2 βˆ’ πœ† + 2)(πœ†2 + πœ† + 3) = 0 ο‚· (πœ†2 βˆ’ πœ† + 2) = 0 πœ†1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž πœ†1,2 = βˆ’(βˆ’1) Β± √(βˆ’1)2 βˆ’ 4(1)(2) 2(1) πœ†1,2 = 1 Β± √1 βˆ’ 8 2 πœ†1,2 = 1 Β± √7𝑖 2 πœ†1 = 1 2 + 1 2 √7𝑖 and πœ†2 = 1 2 βˆ’ 1 2 √7𝑖 ο‚· (πœ†2 + πœ† + 3) = 0 πœ†3,4 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž πœ†3,4 = βˆ’(1) Β± √(1)2 βˆ’ 4(1)(3) 2(1)
  • 7. πœ†3,4 = βˆ’1 Β± √1 βˆ’ 12 2 πœ†3,4 = βˆ’1 Β± √11𝑖 2 πœ†3 = βˆ’ 1 2 + 1 2 √11𝑖 and πœ†4 = βˆ’ 1 2 βˆ’ 1 2 √11𝑖 So, the equation is: 𝑦 = 𝑒 1 2 π‘₯ (𝐢1 cos 1 2 √7π‘₯ + 𝐢2 sin 1 2 √7π‘₯) + π‘’βˆ’ 1 2 π‘₯ (𝐢3 cos 1 2 √11 π‘₯ + 𝐢4 sin 1 2 √11 π‘₯) 5. 𝑑6 𝑦 𝑑π‘₯6 βˆ’ 4 𝑑5 𝑦 𝑑π‘₯5 + 16 𝑑4 𝑦 𝑑π‘₯4 βˆ’ 12 𝑑3 𝑦 𝑑π‘₯3 + 41 𝑑2 𝑦 𝑑π‘₯2 βˆ’ 8 𝑑𝑦 𝑑π‘₯ + 26𝑦 = 0 Characteristic equation is πœ†6 βˆ’ 4πœ†5 + 16πœ†4 βˆ’ 12πœ†3 + 41πœ†2 βˆ’ 8πœ† + 26 = 0 (πœ†4 + 3πœ†2 + 2)(πœ†2 βˆ’ 4πœ† + 13) = 0 (πœ†2 + 1)(πœ†2 + 2)(πœ†2 βˆ’ 4πœ† + 13) = 0 ο‚· (πœ†2 + 1) = 0 πœ†1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž πœ†1,2 = 0 Β± √0 βˆ’ 4(1)(1) 2(1) πœ†1,2 = Β±βˆšβˆ’4 2 πœ†1,2 = Β±2𝑖 2 πœ†1 = 𝑖 and πœ†2 = βˆ’π‘– ο‚· (πœ†2 + 2) = 0 πœ†3,4 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž πœ†3,4 = 0 Β± √0 βˆ’ 4(1)(2) 2(1)
  • 8. πœ†3,4 = Β±βˆšβˆ’8 2 πœ†3,4 = Β±2√2𝑖 2 πœ†3 = √2𝑖 and πœ†4 = βˆ’βˆš2𝑖 ο‚· (πœ†2 βˆ’ 4πœ† + 13) = 0 πœ†5,6 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž πœ†5,6 = βˆ’(βˆ’4) Β± √(βˆ’4)2 βˆ’ 4(1)(13) 2(1) πœ†5,6 = 4 Β± √16 βˆ’ 52 2 πœ†5,6 = 4 Β± 6𝑖 2 πœ†5 = 2 + 3𝑖 and πœ†6 = 2 βˆ’ 3𝑖 So, the solution is 𝑦 = 𝐢1 cos π‘₯ + 𝐢1 sin π‘₯ + 𝑒2π‘₯(𝐢3 cos 3π‘₯ + 𝐢4 sin 3π‘₯) + 𝐢5 cos √2π‘₯ + 𝐢5 sin √2π‘₯
  • 9. TASK III (March 7th, 2014) 1. 𝑑3 π‘ž 𝑑𝑑3 βˆ’ 5 𝑑2 π‘ž 𝑑𝑑2 + 25 π‘‘π‘ž 𝑑𝑑 βˆ’ 125π‘ž = βˆ’60𝑒7𝑑 y(0)=0, y’(0)=1, y”(0)=2 2. 𝑦(𝐼𝑉) βˆ’ 6𝑦′′′ + 16𝑦′′ + 54𝑦′ βˆ’ 225𝑦 = 100π‘’βˆ’2π‘₯ 𝑦(0) = 𝑦′(0) = 𝑦′′(0) = 𝑦′′′(0) = 1 Solution: 1. 𝑑3 π‘ž 𝑑𝑑3 βˆ’ 5 𝑑2 π‘ž 𝑑𝑑2 + 25 π‘‘π‘ž 𝑑𝑑 βˆ’ 125π‘ž = βˆ’60𝑒7𝑑 y(0)=0, y’(0)=1, y”(0)=2 Quadratic equation: πœ†3 βˆ’ 5πœ†2 + 25πœ† βˆ’ 125 = βˆ’60𝑒7𝑑 Y= yl + yr πœ†3 βˆ’ 5πœ†2 + 25πœ† βˆ’ 125 = 0 (πœ† βˆ’ 5)(πœ† + 5𝑖)(πœ† βˆ’ 5𝑖) = 0 𝑦𝑙 = 𝑐1 𝑒5𝑑 + 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑 π‘¦π‘Ÿ = 𝐴0 𝑒7𝑑 π‘¦π‘Ÿ β€² = 7𝐴0 𝑒7𝑑 π‘¦π‘Ÿ β€²β€² = 49𝐴0 𝑒7𝑑 π‘¦π‘Ÿ β€²β€²β€² = 343𝐴0 𝑒7𝑑 𝑦′′′ βˆ’ 5𝑦′′ + 25𝑦 βˆ’ 125𝑦 = βˆ’60𝑒7𝑑 343𝐴0 𝑒7𝑑 βˆ’ 245𝐴0 𝑒7𝑑 + 175𝐴0 𝑒7𝑑 βˆ’ 125𝐴0 𝑒7𝑑 = βˆ’60𝑒7𝑑 148𝐴0 𝑒7𝑑 = βˆ’60𝑒7𝑑 𝐴0 = βˆ’ 60 148 = βˆ’ 15 37 π‘¦π‘Ÿ = βˆ’ 15 37 𝑒7𝑑
  • 10. Then, we got the equation is equal to Y= yl + yr 𝑦(𝑑) = 𝑐1 𝑒5𝑑 + 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑 βˆ’ 15 37 𝑒7𝑑 Now, we are going to find the value of c1, c2, and c3. y(0)=0 0 = 𝑐1 + 𝑐2 βˆ’ 15 37 𝑐1 + 𝑐2 = 15 37 ........................................ (1) y’(0)=1 𝑦′ (𝑑) = 5𝑐1 𝑒5𝑑 βˆ’ 5𝑐2 sin 5𝑑 + 5𝑐3 cos 5𝑑 βˆ’ 105 37 𝑒7𝑑 1 = 5𝑐1 + 5𝑐3 βˆ’ 105 37 𝑐1 + 𝑐3 = 142 185 .................................... (2) y”(0)=2 𝑦′′ (𝑑) = 25𝑐1 𝑒5𝑑 βˆ’ 25𝑐2 cos 5𝑑 βˆ’ 25𝑐3 sin 5𝑑 βˆ’ 735 37 𝑒7𝑑 2 = 25𝑐1 βˆ’ 25𝑐2 βˆ’ 735 37 25𝑐1 βˆ’ 25𝑐2 = 809 37 𝑐1 βˆ’ 𝑐2 = 809 925 ....................................... (3) Elimination of 𝑐2 from (1) and (3) 𝑐1 βˆ’ 𝑐2 = 809 925 ....................................... (3) 𝑐1 + 𝑐2 = 15 37 ........................................ (1) 2𝑐1 = 809 + 375 925 𝑐1 = 592 925 From (3), we can get the value of c2 by substituting the value of c1. 𝑐1 βˆ’ 𝑐2 = 809 925 ....................................... (3) +
  • 11. 592 925 βˆ’ 𝑐2 = 809 925 𝑐2 = βˆ’ 217 925 From (2), we can get the value of c3 by substituting the value of c1. 𝑐1 + 𝑐3 = 142 185 .................................... (2) 592 925 + 𝑐3 = 142 185 𝑐3 = 118 925 After getting the value of c1, c2, and c3, then the equation is: 𝑦(𝑑) = 592 925 𝑒5𝑑 βˆ’ 217 925 cos 5𝑑 + 118 925 sin 5𝑑 βˆ’ 15 37 𝑒7𝑑 2. 𝑦(𝐼𝑉) βˆ’ 6𝑦′′′ + 16𝑦′′ + 54𝑦′ βˆ’ 225𝑦 = 100π‘’βˆ’2π‘₯ 𝑦(0) = 𝑦′(0) = 𝑦′′(0) = 𝑦′′′(0) = 1 Quadratic equation: πœ†4 βˆ’ 6πœ†3 + 16πœ†2 + 54πœ† βˆ’ 225 = 100π‘’βˆ’2π‘₯ 𝑦 = 𝑦𝑙 + π‘¦π‘Ÿ πœ†4 βˆ’ 6πœ†3 + 16πœ†2 + 54πœ† βˆ’ 225 = 0 By using Horner method and ABC formula, so that the roots are gotten: πœ†1 = 3 πœ†3 = 3 + 4𝑖 πœ†2 = βˆ’3 πœ†4 = 3 βˆ’ 4𝑖 𝑦𝑙 = 𝑐1 𝑒3𝑑 + 𝑐2 π‘’βˆ’3𝑑 + 𝑒3𝑑 (𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) π‘¦π‘Ÿ = 𝐴0 π‘’βˆ’2π‘₯ π‘¦π‘Ÿ β€² = βˆ’2𝐴0 π‘’βˆ’2𝑑
  • 12. π‘¦π‘Ÿ β€²β€² = 4𝐴0 π‘’βˆ’2𝑑 π‘¦π‘Ÿ β€²β€²β€² = βˆ’8𝐴0 π‘’βˆ’2𝑑 π‘¦π‘Ÿ (𝐼𝑉) = 16𝐴0 π‘’βˆ’2𝑑 𝑦(𝐼𝑉) βˆ’ 6𝑦′′′ + 16𝑦′′ + 54𝑦′ βˆ’ 225𝑦 = 100π‘’βˆ’2𝑑 16𝐴0 π‘’βˆ’2𝑑 + 48𝐴0 π‘’βˆ’2𝑑 + 64𝐴0 π‘’βˆ’2𝑑 βˆ’ 108𝐴0 π‘’βˆ’2𝑑 βˆ’ 225𝐴0 π‘’βˆ’2𝑑 = 100π‘’βˆ’2𝑑 βˆ’205𝐴0 π‘’βˆ’2𝑑 = 100π‘’βˆ’2𝑑 𝐴0 = βˆ’ 100 205 = βˆ’ 20 41 So, the value of yr is π‘¦π‘Ÿ = βˆ’ 20 41 π‘’βˆ’2𝑑 𝑦 = 𝑐1 𝑒3𝑑 + 𝑐2 π‘’βˆ’3𝑑 + 𝑒3𝑑 (𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) βˆ’ 20 41 π‘’βˆ’2𝑑 Now, we are going to find the value of c1, c2, and c3. y(0) = 1 1 = 𝑐1 + 𝑐2 + 𝑐3 βˆ’ 20 41 𝑐1 + 𝑐2 + 𝑐3 = 61 41 ....................................... (1) y’(0)=1 𝑦′ = 3𝑐1 𝑒3𝑑 βˆ’ 3𝑐2 π‘’βˆ’3𝑑 + 3𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) + 𝑒3𝑑(βˆ’4𝑐3 sin 4𝑑 + 4𝑐4 cos 4𝑑) + 40 41 π‘’βˆ’2𝑑 1 = 3𝑐1 βˆ’ 3𝑐2 + 3𝑐3 + 4𝑐4 + 40 41 3𝑐1 βˆ’ 3𝑐2 + 3𝑐3 + 4𝑐4 = 1 41 ........................ (2) y’’(0)=1
  • 13. 𝑦′′ = 9𝑐1 𝑒3𝑑 + 9𝑐2 π‘’βˆ’3𝑑 + 9𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) + 3𝑒3𝑑(βˆ’4𝑐3 sin 4𝑑 + 4𝑐4 cos 4𝑑) + 3𝑒3𝑑(βˆ’4𝑐3 sin 4𝑑 + 4𝑐4 cos 4𝑑) βˆ’ 16𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) + 80 41 π‘’βˆ’2𝑑 1 = 9𝑐1 + 9𝑐2 + 9𝑐3 + 12𝑐4 + 12𝑐4 βˆ’ 16𝑐3 βˆ’ 80 41 1 = 9(𝑐1 + 𝑐2 + 𝑐3) + 24𝑐4 βˆ’ 16𝑐3 βˆ’ 80 41 121 41 = 9( 61 41 ) + 24𝑐4 βˆ’ 16𝑐3 βˆ’ 428 41 = 24𝑐4 βˆ’ 16𝑐3 2𝑐3 βˆ’ 3𝑐4 = 107 82 .......................................... (3) y’’’(0)=1 𝑦′′′ = 27𝑐1 𝑒3𝑑 βˆ’ 27𝑐2 π‘’βˆ’3𝑑 + 75𝑒3𝑑(𝑐3 cos 4𝑑 + 𝑐4 sin 4𝑑) βˆ’ 100𝑒3𝑑(βˆ’π‘3 sin 4𝑑 + 𝑐4 cos 4𝑑) + 160 41 π‘’βˆ’2𝑑 1 = 27𝑐1 βˆ’ 27𝑐2 + 75𝑐3 βˆ’ 100𝑐4 + 160 41 27𝑐1 βˆ’ 27𝑐2 + 75𝑐3 βˆ’ 100𝑐4 = βˆ’ 119 41 ........ (4) To get the value of c1, c2, c3, and c4, we can use elimination and substituion method from the above equations. From (4) and (2), we can get the new equation: 27𝑐1 βˆ’ 27𝑐2 + 75𝑐3 βˆ’ 100𝑐4 = βˆ’ 119 41 ........ (4) 27𝑐1 βˆ’ 27𝑐2 + 27𝑐3 + 36𝑐4 = 9 41 ................ (2) 43𝑐3 βˆ’ 136𝑐4 = βˆ’ 128 41 6𝑐3 βˆ’ 176𝑐4 = βˆ’ 16 41 ..................................... (5) From (5) and (3), we can get the value of c4. +
  • 14. 6𝑐3 βˆ’ 176𝑐4 = βˆ’ 16 41 ..................................... (5) 6𝑐3 βˆ’ 9𝑐4 = 321 82 ... ....................................... (3) βˆ’8𝑐4 = βˆ’32 βˆ’ 321 82 𝑐4 = βˆ’353 656 From (3), we can get the value of c3. 2𝑐3 βˆ’ 3( βˆ’353 656 ) = 107 82 .......................................... (3) 2𝑐3 = 1915 656 𝑐3 = 1915 1315 From (1), we get: 𝑐1 + 𝑐2 + 1915 1315 = 61 41 ....................................... (1) 𝑐1 + 𝑐2 = 37 1312 ................................................ (6) From (2), we get: 3𝑐1 βˆ’ 3𝑐2 + 3( 1915 1315 ) + 4( βˆ’353 656 ) = 1 41 ........................ (2) 3𝑐1 βˆ’ 3𝑐2 = 32 βˆ’ 5745 βˆ’ 2824 1312 3𝑐1 βˆ’ 3𝑐2 = βˆ’ 8537 1312 𝑐1 βˆ’ 𝑐2 = βˆ’ 8537 3936 ................................................ (7) From (6) and (7), we can get the value of c1 and c2 by elimination method. 𝑐1 + 𝑐2 = 37 1312 ................................................ (6) +
  • 15. 𝑐1 βˆ’ 𝑐2 = βˆ’ 8537 3936 ............................................. (7) 2𝑐1 = βˆ’8537 + 111 3936 2𝑐1 = βˆ’8426 3936 𝑐1 = βˆ’4213 3936 From (7), we can get the value of c2. βˆ’4213 3936 βˆ’ 𝑐2 = βˆ’ 8537 3936 ............................................. (7) 𝑐2 = 8537 βˆ’ 4213 3936 𝑐2 = 1081 656 After getting the value of c1, c2, c3, and c4, we get the characteristic value. 𝑦 = βˆ’ 4213 3936 𝑒3𝑑 + 1081 656 π‘’βˆ’3𝑑 + 𝑒3𝑑 ( 1915 1315 cos 4𝑑 βˆ’ 353 656 sin 4𝑑) βˆ’ 20 41 π‘’βˆ’2𝑑 +
  • 16. TASK IV (March 13th, 2014) 1. 𝑑2 π‘ž 𝑑𝑑2 + 1000 π‘‘π‘ž 𝑑𝑑 + 25000π‘ž = 24 π‘ž(0) = π‘žβ€²(0) = 0 2. 𝑑2 𝑦 𝑑𝑑2 βˆ’ 4 𝑑𝑦 𝑑𝑑 + 𝑦 = 2𝑑3 + 3𝑑2 βˆ’ 1 𝑦(0) = 𝑦′(0) = 1 Solution: 1. π‘žβ€²β€² + 1000π‘žβ€² + 25000π‘ž = 24 Quadratic equation: 𝑑2 + 1000𝑑 + 25000 = 0 𝑑1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž 𝑑1,2 = βˆ’1000 Β± √(1000)2 βˆ’ 4(1)(25000) 2(1) 𝑑1,2 = βˆ’1000 Β± √900000 2 𝑑1,2 = βˆ’1000 Β± 300√10 2 𝑑1,2 = βˆ’500 Β± 150√10 𝑑1 = βˆ’500 + 150√10 and 𝑑2 = βˆ’500 βˆ’ 150√10 π‘žπ‘™ = 𝑐1 𝑒(βˆ’500+150√10)𝑑 + 𝑐2 𝑒(βˆ’500βˆ’150√10)𝑑 π‘ž π‘Ÿ = 𝐴0 π‘žβ€² π‘Ÿ = 0 π‘žβ€²β€² π‘Ÿ = 0 π‘žβ€²β€² + 1000π‘žβ€² + 25000π‘ž = 24 0 + 1000(0) + 25000(𝐴0) = 24 𝐴0 = 3 3125 , then π‘ž π‘Ÿ = 3 3125
  • 17. π‘ž = π‘žπ‘™ + π‘ž π‘Ÿ π‘ž(𝑑) = 𝑐1 𝑒(βˆ’500+150√10)𝑑 + 𝑐2 𝑒(βˆ’500βˆ’150√10)𝑑 + 3 3125 π‘ž(0) = 0 0 = 𝑐1 + 𝑐2 + 3 3125 𝑐1 + 𝑐2 = βˆ’ 3 3125 ...................................(1) π‘žβ€²(𝑑) = (βˆ’500 + 150√10)𝑐1 𝑒(βˆ’500+150√10)𝑑 + (βˆ’500 βˆ’ 150√10)𝑐2 𝑒(βˆ’500βˆ’150√10)𝑑 π‘žβ€²(0) = 0 0 = (βˆ’500 + 150√10)𝑐1 + (βˆ’500 βˆ’ 150√10)𝑐2 ........................... (2) By using elimination method, we can find the value of c1 from (1) and (2). (βˆ’500 βˆ’ 150√10)𝑐1 + (βˆ’500 βˆ’ 150√10)𝑐2 = βˆ’ 3 3125 (βˆ’500 βˆ’ 150√10) (βˆ’500 + 150√10)𝑐1 + (βˆ’500 βˆ’ 150√10)𝑐2 = 0 βˆ’300√10𝑐1 = βˆ’ 3 3125 (βˆ’500 βˆ’ 150√10) 𝑐1 = βˆ’5√10 βˆ’ 15 3125 By using (1), we can find the value of c2. 𝑐1 + 𝑐2 = βˆ’ 3 3125 βˆ’5√10 βˆ’ 15 3125 + 𝑐2 = βˆ’ 3 3125 𝑐2 = 5√10 + 12 3125 After finding the value of c1 and c2, we get the equation. π‘ž(𝑑) = ( βˆ’5√10 βˆ’ 15 3125 ) 𝑒(βˆ’500+150√10)𝑑 + ( 5√10 + 12 3125 ) 𝑒(βˆ’500βˆ’150√10)𝑑 + 3 3125 –
  • 18. 2. 𝑦′′ βˆ’ 4𝑦′ + 𝑦 = 2𝑑3 + 3𝑑2 βˆ’ 1 Quadratic equation: 𝑑2 βˆ’ 4𝑑 + 1 = 0 𝑑1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž 𝑑1,2 = βˆ’(βˆ’4) Β± √(βˆ’4)2 βˆ’ 4(1)(1) 2(1) 𝑑1,2 = 4 Β± √12 2 𝑑1,2 = 4 Β± 2√3 2 𝑑1,2 = 2 Β± √3 𝑑1 = 2 + √3 and 𝑑2 = 2 βˆ’ √3 𝑦𝑙 = 𝑐1 𝑒(2+√3)𝑑 + 𝑐2 𝑒(2βˆ’βˆš3)𝑑 π‘¦π‘Ÿ = 𝐴3 𝑑3 + 𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0 𝑦′ π‘Ÿ = 3𝐴3 𝑑2 + 2𝐴2 𝑑 + 𝐴1 𝑦′′ π‘Ÿ = 6𝐴3 𝑑 + 2𝐴2 𝑦′′ βˆ’ 4𝑦′ + 𝑦 = 2𝑑3 + 3𝑑2 βˆ’ 1 (6𝐴3 𝑑 + 2𝐴2) βˆ’ 4(3𝐴3 𝑑2 + 2𝐴2 𝑑 + 𝐴1) + (𝐴3 𝑑3 + 𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0) = 2𝑑3 + 3𝑑2 βˆ’ 1 𝐴3 𝑑3 + (βˆ’12𝐴3 + 𝐴2)𝑑2 + (6𝐴3 βˆ’ 8𝐴2 + 𝐴1)𝑑 + 𝐴1 + 𝐴0 = 2𝑑3 + 3𝑑2 βˆ’ 1 Equation similarity: 𝐴3 = 2 βˆ’12𝐴3 + 𝐴2 = 3 βˆ’12(2) + 𝐴2 = 3 𝐴2 = 27 6𝐴3 βˆ’ 8𝐴2 + 𝐴1 = 0 6(2) βˆ’ 8(27) + 𝐴1 = 0 𝐴1 = 204
  • 19. 𝐴1 + 𝐴0 = βˆ’1 204 + 𝐴0 = βˆ’1 𝐴0 = βˆ’205 π‘¦π‘Ÿ = 2𝑑3 + 27𝑑2 + 204𝑑 βˆ’ 205 𝑦 = 𝑦𝑙 + π‘¦π‘Ÿ 𝑦(𝑑) = 𝑐1 𝑒(2+√3)𝑑 + 𝑐2 𝑒(2βˆ’βˆš3)𝑑 + 2𝑑3 + 27𝑑2 + 204𝑑 βˆ’ 205 𝑦(0) = 1 1 = 𝑐1 + 𝑐2 βˆ’ 205 𝑐1 + 𝑐2 = 206 .........................(1) 𝑦′(𝑑) = (2 + √3)𝑐1 𝑒(2+√3)𝑑 + (2 βˆ’ √3)𝑐2 𝑒(2βˆ’βˆš3)𝑑 + 6𝑑2 + 54𝑑 + 204 𝑦′(0) = 1 1 = (2 + √3)𝑐1 + (2 βˆ’ √3)𝑐2 + 204 (2 + √3)𝑐1 + (2 βˆ’ √3)𝑐2 = βˆ’203 ........................... (2) By using elimination and substitution method, the value of c1 and c2 can be obtained from (1) and (2). βˆ’203 = (2 + √3)𝑐1 + (2 βˆ’ √3)𝑐2........................... (2) 206 = (2 βˆ’ √3)𝑐1 + (2 βˆ’ √3)𝑐2 ...................................(1) 2√3𝑐1 = βˆ’203 βˆ’ 206(2 βˆ’ √3) 2√3𝑐1 = βˆ’715 + 206√3 𝑐1 = βˆ’715√3 + 618 6 𝑐1 + 𝑐2 = 206 ( βˆ’715√3 + 618 6 ) + 𝑐2 = 206 𝑐2 = 715√3 + 618 6 𝑦(𝑑) = ( βˆ’715√3+618 6 ) 𝑒(2+√3)𝑑 + ( 715√3+618 6 ) 𝑒(2βˆ’βˆš3)𝑑 + 2𝑑3 + 27𝑑2 + 204𝑑 βˆ’ 205 –
  • 20. TASK V (March 20th, 2014) 1. 𝑑2 π‘₯ 𝑑𝑑2 + 4 𝑑π‘₯ 𝑑𝑑 + 8π‘₯ = (20𝑑2 + 16𝑑 βˆ’ 78)𝑒2𝑑 y(0)=y’(0)=0 2. 𝑑3 π‘ž 𝑑𝑑3 βˆ’ 5 𝑑2 π‘ž 𝑑𝑑2 + 25 π‘‘π‘ž 𝑑𝑑 βˆ’ 125π‘ž = (βˆ’500𝑑2 + 465𝑑 βˆ’ 387)𝑒2𝑑 q(0)=q’(0)= q’’(0)=0 Solution: 1. 𝑑2 π‘₯ 𝑑𝑑2 + 4 𝑑π‘₯ 𝑑𝑑 + 8π‘₯ = (20𝑑2 + 16𝑑 βˆ’ 78)𝑒2𝑑 y(0)=y’(0)=0 quadratic equation is πœ†2 + 4πœ† + 8 = 0 πœ†1,2 = βˆ’π‘ Β± βˆšπ‘2 βˆ’ 4π‘Žπ‘ 2π‘Ž πœ†1,2 = βˆ’4 Β± √42 βˆ’ 4(1)(8) 2(1) πœ†1,2 = βˆ’4 Β± βˆšβˆ’16 2 πœ†1,2 = βˆ’2 Β± 2𝑖 𝑦𝑙 = π‘’βˆ’2𝑑 (𝑐1 cos 2𝑑 + 𝑐2 sin 2𝑑) π‘¦π‘Ÿ = (𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)𝑒2𝑑 𝑦′ π‘Ÿ = (2𝐴2 𝑑 + 𝐴1)𝑒2𝑑 + (𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)(2𝑒2𝑑) 𝑦′′ π‘Ÿ = 2𝐴2 𝑒2𝑑 + (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)(4𝑒2𝑑) 𝑦′′ + 4𝑦′ + 8𝑦 = (20𝑑2 + 16𝑑 βˆ’ 78)𝑒2𝑑 2𝐴2 𝑒2𝑑 + (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (2𝐴2 𝑑 + 𝐴1)(2𝑒2𝑑) + (𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)(4𝑒2𝑑) + 4{(2𝐴2 𝑑 + 𝐴1)𝑒2𝑑 + (𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)(2𝑒2𝑑)} + 8{(𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)𝑒2𝑑} = (20𝑑2 + 16𝑑 βˆ’ 78)𝑒2𝑑 (2𝐴2 + 8𝐴1 + 20𝐴0)𝑒2𝑑 + (16𝐴2 + 20𝐴1)𝑑𝑒2𝑑 + (20𝐴2)𝑑2 𝑒2𝑑 = (20𝑑2 + 16𝑑 βˆ’ 78)𝑒2𝑑 ο‚· 20𝐴2 = 20 𝐴2 = 1
  • 21. ο‚· 16𝐴2 + 20𝐴1 = 16 16(1) + 20𝐴1 = 16 20𝐴1 = 0 𝐴1 = 0 ο‚· 2𝐴2 + 8𝐴1 + 20𝐴0 = βˆ’78 2(1) + 8(0) + 20𝐴0 = βˆ’78 20𝐴0 = βˆ’78 βˆ’ 2 20𝐴0 = βˆ’80 𝐴0 = βˆ’4 π‘¦π‘Ÿ = (𝑑2 βˆ’ 4)𝑒2𝑑 y = yl + yr 𝑦(𝑑) = π‘’βˆ’2𝑑(𝑐1 cos 2𝑑 + 𝑐2 sin 2𝑑) + (𝑑2 βˆ’ 4)𝑒2𝑑 𝑦′(𝑑) = (βˆ’2π‘’βˆ’2𝑑)(𝑐1 cos 2𝑑 + 𝑐2 sin 2𝑑) + π‘’βˆ’2𝑑(βˆ’2𝑐1 sin 2𝑑 + 2𝑐2 cos 2𝑑) + 2𝑑𝑒2𝑑 + (𝑑2 βˆ’ 4)(2𝑒2𝑑) 𝑦(0) = 0 0 = 𝑐1 βˆ’ 4 𝑐1 = 4 𝑦′(0) = 0 0 = βˆ’2𝑐1 + 2𝑐2 βˆ’ 8 8 = βˆ’2(4) + 2𝑐2 𝑐2 = 8 𝑦(𝑑) = π‘’βˆ’2𝑑(4 cos 2𝑑 + 8 sin 2𝑑) + (𝑑2 βˆ’ 4)𝑒2𝑑 2. 𝑑3 π‘ž 𝑑𝑑3 βˆ’ 5 𝑑2 π‘ž 𝑑𝑑2 + 25 π‘‘π‘ž 𝑑𝑑 βˆ’ 125π‘ž = (βˆ’500𝑑2 + 465𝑑 βˆ’ 387)𝑒2𝑑 q(0)=q’(0)= q’’(0)=0 Quadratic equation is: πœ†3 βˆ’ 5πœ†2 + 25πœ† βˆ’ 125 = 0
  • 22. πœ†1 = 5 πœ†2 = 5𝑖 πœ†3 = βˆ’5𝑖 𝑦𝑙 = 𝑐1 𝑒5𝑑 + 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑 π‘¦π‘Ÿ = (𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)𝑒2𝑑 𝑦′ π‘Ÿ = (2𝐴2 𝑑 + 𝐴1)𝑒2𝑑 + (𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)(2𝑒2𝑑 ) = 2𝐴2 𝑑𝑒2𝑑 + 𝐴1 𝑒2𝑑 + 2𝐴2 𝑑2 𝑒2𝑑 + 2𝐴1 𝑑𝑒2𝑑 + 2𝐴0 𝑒2𝑑 𝑦′′ π‘Ÿ = 2𝐴2 𝑒2𝑑 + 8𝐴2 𝑑𝑒2𝑑 + 2𝐴1 𝑒2𝑑 + 4𝐴2 𝑑𝑒2𝑑 + 4𝐴2 𝑑2 𝑒2𝑑 + 2𝐴1 𝑒2𝑑 + 4𝐴1 𝑑𝑒2𝑑 + 4𝐴0 𝑒2𝑑 𝑦′′′ π‘Ÿ = 12𝐴2 𝑒2𝑑 + 12𝐴1 𝑒2𝑑 + 8𝐴0 𝑒2𝑑 + 24𝐴2 𝑑𝑒2𝑑 + 8𝐴1 𝑑𝑒2𝑑 + 8𝐴2 𝑑2 𝑒2𝑑 𝑦′′′ βˆ’ 5𝑦′′ + 25𝑦′ βˆ’ 125𝑦 = (βˆ’500𝑑2 + 465𝑑 βˆ’ 387)𝑒2𝑑 12𝐴2 𝑒2𝑑 + 12𝐴1 𝑒2𝑑 + 8𝐴0 𝑒2𝑑 + 24𝐴2 𝑑𝑒2𝑑 + 8𝐴1 𝑑𝑒2𝑑 + 8𝐴2 𝑑2 𝑒2𝑑 βˆ’ 5{2𝐴2 𝑒2𝑑 + 8𝐴2 𝑑𝑒2𝑑 + 2𝐴1 𝑒2𝑑 + 4𝐴2 𝑑𝑒2𝑑 + 4𝐴2 𝑑2 𝑒2𝑑 + 2𝐴1 𝑒2𝑑 + 4𝐴1 𝑑𝑒2𝑑 + 4𝐴0 𝑒2𝑑 } + 25{2𝐴2 𝑑𝑒2𝑑 + 𝐴1 𝑒2𝑑 + 2𝐴2 𝑑2 𝑒2𝑑 + 2𝐴1 𝑑𝑒2𝑑 + 2𝐴0 𝑒2𝑑} βˆ’ 125{(𝐴2 𝑑2 + 𝐴1 𝑑 + 𝐴0)𝑒2𝑑} = (βˆ’500𝑑2 + 465𝑑 βˆ’ 387)𝑒2𝑑 (2𝐴2 + 17𝐴1 βˆ’ 87𝐴0)𝑒2𝑑 + (34𝐴2 βˆ’ 87𝐴1)𝑑𝑒2𝑑 + (βˆ’87𝐴2)𝑑2 𝑒2𝑑 = βˆ’500𝑑2 𝑒2𝑑 + 465𝑑𝑒2𝑑 βˆ’ 387𝑒2𝑑 ο‚· βˆ’87𝐴2 = βˆ’500 𝐴2 = 500 87 ο‚· 34𝐴2 βˆ’ 87𝐴1 = 465 34 ( 500 87 ) βˆ’ 87𝐴1 = 465 𝐴1 = βˆ’23455 7569 ο‚· 2𝐴2 + 17𝐴1 βˆ’ 87𝐴0 = βˆ’387 2 ( 500 87 ) + 17 ( βˆ’23455 7569 ) βˆ’ 87𝐴0 = βˆ’387 𝐴0 = 2617468 658503
  • 23. π‘¦π‘Ÿ = ( 500 87 𝑑2 βˆ’ 23455 7569 𝑑 + 2617468 658503 ) 𝑒2𝑑 𝑦 = 𝑦𝑙 + π‘¦π‘Ÿ 𝑦(𝑑) = 𝑐1 𝑒5𝑑 + 𝑐2 cos 5𝑑 + 𝑐3 sin 5𝑑 + ( 500 87 𝑑2 βˆ’ 23455 7569 𝑑 + 2617468 658503 ) 𝑒2𝑑 𝑦′ (𝑑) = 5𝑐1 𝑒5𝑑 βˆ’ 5𝑐2 sin 5𝑑 + 5𝑐3 cos 5𝑑 + ( 1000 87 𝑑 βˆ’ 23455 7569 ) 𝑒2𝑑 + ( 500 87 𝑑2 βˆ’ 23455 7569 𝑑 + 2617468 658503 ) (2𝑒2𝑑) 𝑦′′(𝑑) = 25𝑐1 𝑒5𝑑 βˆ’ 25𝑐2 cos5𝑑 βˆ’ 25𝑐3 sin5𝑑 + 1000 87 𝑒2𝑑 + ( 1000 87 𝑑 βˆ’ 23455 7569 ) (2𝑒2𝑑) + ( 1000 87 𝑑 βˆ’ 23455 7569 ) (2𝑒2𝑑) + ( 500 87 𝑑2 βˆ’ 23455 7569 𝑑 + 2617468 658503 ) (4𝑒2𝑑) 𝑦(0) = 0 0 = 𝑐1 + 𝑐2 + 2617468 658503 𝑐1 + 𝑐2 = βˆ’ 2617468 658503 ................................... (1) 𝑦′(0) = 0 0 = 5𝑐1 + 5𝑐3 βˆ’ 23455 7569 + 5234936 658503 5𝑐1 + 5𝑐3 = βˆ’ 3194351 658503 𝑐1 + 𝑐3 = βˆ’ 3194351 3292515 .................................... (2) 𝑦′′(0) = 0 0 = 25𝑐1 βˆ’ 25𝑐2 + 1000 87 βˆ’ 46910 7569 βˆ’ 46910 7569 + 10469872 658503 25𝑐1 βˆ’ 25𝑐2 = βˆ’ 9876532 658503 .................................... (3) 25𝑐1 + 25𝑐2 = βˆ’ 65436700 658503 ................................... (1) 50𝑐1 = βˆ’ 75313232 658503 𝑐1 = βˆ’ 75313232 32925150 +
  • 24. From equation (1), we get the value of c2. 𝑐2 = βˆ’ 2617468 658503 + 75313232 32925150 𝑐2 = βˆ’ 55560168 32925150 From equation (2), we get the value of c3. 𝑐3 = βˆ’ 3194351 3292515 + 75313232 32925150 𝑐3 = 43369722 32925150 𝑦(𝑑) = βˆ’ 75313232 32925150 𝑒5𝑑 βˆ’ 55560168 32925150 cos 5𝑑 + 43369722 32925150 sin 5𝑑 + ( 500 87 𝑑2 βˆ’ 23455 7569 𝑑 + 2617468 658503 ) 𝑒2𝑑