McGraw Hill Integrated II, 2012
MH
McGraw Hill Integrated II, 2012 View details
Standardized Test Practice

Exercise 1 Page 270

To rationalize a fraction with a binomial denominator, multiply the numerator and denominator of the fraction by the conjugate of the denominator.

H

Practice makes perfect
To rationalize a fraction with a binomial denominator, we multiply the numerator and denominator of the fraction by the conjugate of the denominator. We find the conjugate by changing the sign of the second term of the expression.
Binomial Conjugate
a + b a - b
a - b a + b
In this case, the conjugate of the denominator is 4-sqrt(2).
1/4+sqrt(2)
4-sqrt(2)/(4+sqrt(2))(4-sqrt(2))
4-sqrt(2)/4^2-(sqrt(2))^2
4-sqrt(2)/4^2-2
4-sqrt(2)/16-2
4-sqrt(2)/14
The rationalized expression equals 4-sqrt(2)14, which corresponds to answer H.