Digital Lesson Exponents and Radicals Repeated multiplication can be written in exponential form. aaaaaa a 6 3y 3y 3y (3y) 34 3 exponent base Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 2 For all real numbers a and b and all integers m and n, mn 1. a a a 33 32 33 2 35 243 m n m mn a 2. a an x12 x125 x 7 x5 n 3. a 1n a z 3 13 z 1 a 1 z n 3 Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 3 For all real numbers a and b and all integers m and n, 4. a0 1, a 0 1000 1 5. (ab)m a mbm (3x)4 34 x 4 81x 4 6. (a ) a ( y 2)6 y 2(6) y12 m n mn Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 4 For all real numbers a and b and all integers m and n, 7. a b d 5 m m a m b 2 2 2 d d 2 25 5 8. a a a 2 2 2 (4) 4 42 16 2 2 Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 5 Scientific notation is a convenient way to write very large or very small numbers. c 10 n integer 1 c 10 Example: a.) -3.683 x 107 = -36830000. 7 decimal places b.) 0.495 x 10-5 = 0.00000495 5 decimal places Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 6 A square root of a number is one of its two equal factors. 25 5 5 5 2 A cube root of a number is one of its three equal factors. 64 (4)(4)(4) (4) ab 3 n nth root of a Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 7 The principal nth root of a is the nth root that has the same sign as a. index radical symbol n a radicand 4 81 =3 3 125 = 5 3 is the principal 4th root of 81. 5 is the principal cube root of 125. Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 8 For all real numbers a and b and all positive integers m and n, 1. 2. 3. a 64 a n m 2 4 16 2 3 64 n a n b n ab 3 8 3 27 3 216 6 n 2 m n a n n b 16 8 3 a, b 0 b 16 2 8 Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 9 For all real numbers a and b and all positive integers m and n, 4. m n 3 4 5. 24 12 24 a a 60 60 n 5 6. a mn a n 5 If n is even, n a a. 4 (36)4 36 36 If n is odd, n a a. 5 (36) 36 n n Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 5 10 Example: Rationalize the denominator. 2 2 5 2 5 5 5 5 5 a.) rationalizing factor 5 14 2 5 14 2 14 2 14 2 b.) 5 conjugate 14 2 5 14 10 14 2 10 2 14 4 simplified Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 11 rational exponent 64 23 64 3 2 Example: Simplify the radical expression. a.) b.) 4 24 12 3 3 3 3 2 32 4 32 4 16 2 2 4 2 Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 12 An expression involving radicals is in simplest form when the following are satisfied. 1. All possible factors have been removed from the radical. 24 4 6 2 6 2. The denominators have been rationalized. 3 3 5 3 5 3 5 7 5 7 5 5 7(5) 35 3. The index of the radical is reduced. 3 3 36 12 125 6 125 6 (5) 5 5 5 Copyright © by Houghton Mifflin Company, Inc. All rights reserved. 13