How do you rationalize the denominator of #sqrt7/sqrt5#?

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Answer 1 · 2016-02-09T03:58:29

#(sqrt 15) / 5#

Observe the denominator. Here denominator is #sqrt 5#.

So multiply numerator and denominator by #sqrt 5#, which makes it

#(sqrt 7) / (sqrt 5)# * #(sqrt 5)/(sqrt 5)#

i.e. #(sqrt 15) / 5#

If denominator is of type #a+-sqrt b# type,

multiply it by #a -sqrt b#, if it is #a+sqrt b#.

And by #a+sqrt b#, if it is #a -sqrt b#.