Multiplication and Division of Exponents Notes Multiplication Rule x x x n m n m In order to use this rule the base numbers being multiplied must be the same. Example: 3 x x 4 Written in multiplication form x x x x x x x x Using Rule x 3 4 x 7 7 Example 1 2 2 3 2*2*2 2 5 2*2*2*2*2 3 5 2 8 Example 2 x x x 354 3 5 x x 12 4 Example 3 x x y y z 4 3 Remember x 14 y 34 x 5 y 7 z 4 xx z 1 Example 4 3 5 3 2 (2x y )(3xy )(x y) Multiply coefficients and add exponents of like bases 6x (312) (531) y 6x y 6 9 Example 5 4x (2x y 5xy ) 5 2 2 In order to simplify you must distribute. Since you are multiplying when you distribute you must use the multiplication rule for exponents 8x 52 y 20x 51 2 8x y 20x y 7 6 y 2 You Try Simplify each expression 1. y y 4 y 2 15 x 3 2 2. 3, 4. 5. 6. 6 (3x )(5x) 7 x x x 5 6 3 2 2 4 ab (a b )(a b ) 3 4 2 5 2 12y 3 (4 y )(3y) 4 6 (x y )(x y ) x9y8 Simplify (remember when adding only add coefficients of like terms) 1. 2. 3. 3x 3 (2x 2 5x 2) 8x 2 2x 2x(4x 1) 4 x(x 5) (x 2 6x 8) 4. 6x 5 15 x 4 6x 3 4 x 5 (2x 3 6x) 12 x 6 4x 2 20x x 2 6x 8 5x 2 26x 8 8x 8 24x 6 12x 6 8x 8 36x 6 Division Rule: If the bases are the same subtract the exponents m x mn x n x x 5 x x x x x 2 x x3 x x x 5 OR x 5 3 2 x x x3 Always do top exponent minus bottom exponent Examples 1. 2. 3. x2y6 xy 2 6a 7b 3 2ab 2 x5 x8 x3 x 21 y 62 xy 4 3a 71b 3 2 3a 6b Divide coefficients, subtract exponents of the like bases. x 5 8 x13 133 10 Use multiplication rule x x 3 3 x x on top, then use division rule Special Cases ( zero power): any base raised to a power of zero equals 1 x 1 0 Here is why, when the number in the numerator is the same as the number in the denominator, the quotient is always 1. 2 4 2 * 2 * 2 * 2 1 4 2 2*2*2*2 So it makes sense that 24 44 0 2 2 1 4 2 Examples Simplify 3 4 1. 2. ab 3 ab a 10x 4 y 3 5x 4 y 2 2x 44 y 32 2x 0 y1 2*1y 2y 3 3 41 b a b 1b b 0 3 3 3 3. m10 n 5 10 5 m n 1010 m n 5 5 m n 1*1 1 0 0