Sometimes the denominator might be more complicated and include other numbers as well as the surd. If this is the case you need to multiply the fraction by a number that will cancel out the surd.

Watch this video to learn about the rules of surds. For example, \(\sqrt 4 = 2\) is not a surd. However \(\sqrt 5\) is a surd. If you use a calculator, you will see that \(\sqrt 5 = 2.236067977..