# How do you rationalize the denominator and simplify #12/(sqrt5-1)#?

##### 2 Answers

May 28, 2018

#### Explanation:

Use the identities

#a/a=1# for every non-zero#a# #(a+b)(a-b) = a^2-b^2#

to write

Now, as you can see, the numerator is

The denominator, instead, is written in the same form as the second property written at the beginning:

So, the fraction becomes

May 28, 2018

#### Explanation:

When having a root on the bottom with an extra