1. Find the exact function of sec 23pi/6 (simple answer, including radicals, use intergers or
fractions for any numbers in the expression)
2. Exact value of cos(-5pi/4) ....don\'t use calculator.
3. Find exact value of cos 7pi/4 ....don\'t use calculator.
4. cos s = -1/2 .....what does s = in radians
Solution
1) sec 23pi/6 = 1/ (cos 23pi/6) = 1/ (cos(3pi + 5pi/6)) = -1 / (cos 5pi/6) = 1/cos(pi/6) = 1/ (sqrt(3)
/2 ) = 2/sqrt3
2) cos(-5pi/4) = cos(5pi/4) = cos (pi + pi/4) = -cos(pi/4) = -1/ (1/sqrt2) =- sqrt(2)
3) cos(7pi/4) = cos (pi + 3pi/4) = -cos(3pi/4) = cos(pi/4) =1 / sqrt(2)
4) cos s = -1/2 => s= (2pi/3) or s= (4pi/3).
1. find the exact value of the expression sin -1 (sqrt 22)2. Solv.pdf
1. 1. find the exact value of the expression sin -1 (sqrt 2/2)
2. Solve the equation 4 cos^2 sin theta + 2 cos^2 theta = 0 for solutions over the interval [0
degrees, 360 degrees)
3. Solve the equation for the solutions in the interval [0, 2pi). Use algebraic methods and give
exact values. Support your solutions graphically.
sin (x/2) = 1 sin (x/2)
Solution
-0.59500983952
