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 \(\sqrt 5 = 2.236067977...\) ...

National 5 Working with surds Rules of surds Surds are square roots which can’t be reduced to rational numbers. Some can be simplified using various rules or by rationalising the denominator. Part of ...