4. The sum of any number and 0 is equal to the number. Thus, 0 is called the additive identity . Additive Identity: Words: For any number a , the sum of a and 0 is a . Symbols: a + 0 = 0 + a = a Examples: 5 + 0 = 0 + 5 = 5
5. Multiplicative Identity - the product of any number and 1 is equal to the number, 1 is called the multiplicative identity. ex. 7 * n = 7 Words: For any number a , the product of a and 1 is a . Symbols: a * 1 = 1 * a = a Example: 12 * 1 = 12, 1 * 12 = 12
6. Multiplicative Property of Zero - the product of any number and 0 is equal to 0. ex. 9 * m = 0 Words: For any number a , the product of a and 0 is 0. Symbols: a * 0 = 0 * a = 0 Example: 8 * 0 = 0 * 8 = 0
7. Two numbers whose product is 1 are called multiplicative inverses or reciprocals . Zero has no reciprocal because any number times 0 is 0. ex. 1/3 * 3 = 1 Symbols: a/b * b/a = b/a * a/b = 1 Example: 2/3 * 3/2 = 6/6 = 1