Page 147 - Math Course 2 (Book 1)
P. 147
Simplifying Radical Expressions
Use Conjugates to Rationalize a Use Conjugates to Rationalize a Denominator
Denominator
4
Example Simplify 3 – 5
A. 3 + 5
3
Simplify
5 – 2
4 (3 + )
5
3 = 3 • 5 + 2 The conjugate of B.
5 –
2
5 – 2 5 – 2 5 + 2 is 9 – 5
5 + 2
C. 12 + 4 5
2
3(5 + ) (a – b)(a + b) =
=
2
2
5 –( ) 2 a – b 2
2
D. 12 – 4 5
2 )
2
= 15 + 3 ( ) = 2
2
25 – 2 Answer
2 )
Answer 15 + 3
23
Your Turn!
Rationalizing the Denominator
5 2
Simplify Simplify
2 27
5 3
A. A.
2 2
10 6
B. B.
2 9
6
C. 5 C.
9
10 6
D. D.
2 3
Answer Answer
139
