How do you rationalize #(3sqrt7) /( 5-sqrt7)#?

1 Answer
Chaoyi Z.
May 8, 2015

You can rationalize #(3sqrt(7))/(5-sqrt(7))# by multiplying both the numerator and the denominator with the the denominator's conjugate

In this case, the denominator's conjugate is #sqrt(7)+5#:
#(3sqrt(7) * (sqrt(7)+5) )/(5-sqrt(7) * (sqrt(7)+5) )#

This means the rationalized answer is #(15sqrt(7)+21)/(18)#

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