Answer:

Explanation:
For this case we have the following expression:

And we want to factorize this, the first step on this case would be taking common factor
and we got this:

Now we can apply this case of factorization called difference of perfect squares:

For this case

And if we apply this we got:

Now we can rationalize the expression with the square root on the denominator like this:

And if we replace this we got:

And that would be our final expression.