Properties of Rational Exponents

Section 7.2

Agenda 1.Math Talk Expectations 2.Come up with what

happens when students do not follow expectations

3.Number Talk 4.Review Last weeks test 5.5. Start rational exponents!

Number Talk Devonte received $ 500 which was 115% of a number. He has to give 75% of that number to Larry. How much will Larry receive?

WHAT YOU WILL LEARN:1. Simplify expressions with rational exponents.2. Use properties of rational exponents.3. Write an expression involving rational exponents in simplest form.4. Perform operations with rational exponents.5. Simplify expressions that have variables and rational exponents.6. Write an expression involving variables and rational exponents in simplest form.7. Perform operations with rational exponents and variables.

Properties of Rational Exponents

nmnm aaa

Properties of Rational Exponents:

Property: Example:

1.

2. (am)n = amn

3. (ab)m = ambm

4.

93333 2)23

21(

23

21

6444)4( 3)223(22

3

62349)49( 21

21

21

0,1 aa

a mm

51

25

12521

21

Properties of Rational Exponents (cont.)

0, aaaa nmn

m

Properties of Rational Exponents:

Property: Example:

5.

6.

36666

6 2)21

25(

21

25

0,)( aba

ba

m

mm

32

27

8)278(

31

31

31

Using the Properties

41

21

55

• Simplify the expressions:1.

2.

3.

231

21

)58(

41

44 )32(

More Fun with Properties

31

7

74.

5. 2

31

31

)4

12(

You Try

3

41

41

32

31

33

241

31

31

21

9

18

6

6)24(

)627(

66

• Simplify:1.2.3.4.

5.

More Simplifying

33 164

• Simplify the expressions:1.

2. 4

4

2162

You Try

33 525

• Simplify:1.

2. 3

3

432

Simplest Form - continued

3 54

• In order for a radical to be in simplest form, you have to remove any perfect nth powers and rationalize denominators. Example:

Write in simplest form:1. 2. 5

43

You Try

4

4

87

64

• Write in simplest form:1.

2.

Operations Using Radicals

)6(2)6(7 51

51

• Two radicals expressions are “like radicals” if they have the same index and the same radicand. Example:

• Perform the indicated operation:1. 2. 33 216

You Try

33

43

43

381

)4(3)4(5

• Perform the indicated operation:

1.

2.

Simplifying Expressions Involving Variables

nn x

• Important!

= x when n is odd.

= |x| when n is even.

nn x

Simplifying

3 6125y

• Simplify the expression. Assume all variables are positive:

1. 2.

3. 4.

21

102 )9( vu

48

4

yx

531

21

2

6

zx

xy

You Try

341

32

410

5

21

24

3 9

6

18

)16(

27

tr

rs

yx

hg

z

• Simplify the expression. Assume all variables are positive.

1.2.3.

4.

Writing Variable Expressions in Simplest Form

5 13955 cba

• Write the expression in simplest form. Assume all variables are positive.

1. 2. 37yx

You Try

57

2

4 149412

hg

fed

• Write the expression in simplest form. Assume all variables are positive.

1.

2.

Adding and Subtracting Expressions Involving Variables

yy 65

• Perform the indicated operation. Assume all variables are positive.

1. 2.

3.

31

31

72 xyxy

3 23 5 4053 xxx

You Try

44 5

41

41

662

63

38

xxx

ghgh

xx

• Perform the indicated operations. Assume all variables are positive.

1.

2.

3.