EXPONENTIAL AND LOGARITHMIC FUNCTIONS Real Exponents Scientific Notation A number is in scientific notation when it is in the n form a x 1 0 w he re 1 ≤ a ≤ 1 0 a nd n is a n inte g er. 4 1. Write 9.4 X 10 in standard form Solution: .00094 2. Write 784,000,000 in scientific notation form. 8 Solution: 7.84 X 10 Properties of Exponents Example # 1 Evaluate each expression FG 3 IJ 3 3 1. 2. H 4 K 4 7 36 Solutions: 1. 3 5 2. 4 3 1 Simplifying Expressions Simplify each expression. 1. cs t h 4 7 3 Solutions: 1. s12 t21 x 2 y 5 2. c x h 2 2. y x 5 6 4 Rational Exponents Expressions with rational exponents The properties of exponents are still valid. b = n b for a ny rea l num b e r b ≥ 0 a nd a ny integer n>1. This also holds when b<0 and n is odd. 1 n 1 4 Evaluate 625 1 4 4 Solution 5 = 5 c h 1 2 Evaluate 3 x 21 1 2 1 2 1 2 1 2 = 3 x 3 x 7 =3 7 When the exponent is odd Remember when the exponent is odd, we need to use an absolute value because we can not have negative values. If we did, it would result in complex numbers. Example: Simplify r 7 3 = |r| r Example # 2 Simplify r 9 s 5 t 2 4 Solution: r 4 s 2 t st 1 2 4 5 Solve 616 = x -9 4 625 = x 5 5 4 5 4 5 4 (625) = (x ) raise each side to the 3125 = x 5 4 power Irrational exponents A calculator can be used to approximate the value of an expression with irrational exponents. For 3 ex a m p le, 2 ≈ 3 .3 2 1 9 9 7 0 8 5 . HW # 25 Section 11-1 Pp. 700-702 #20-30 all, 33-43 odds, 75,80