This video is another in the Year 10 Advanced course looking at surds. Having looked at how to add, subtract, multiply and divide them I finish this video looks at what it means to rationalise the denominator. Convention states that we're not permitted to have a surd on the bottom of a fraction and so we use a simple, but effective, trick to help "get rid of the the surd". There are a number of examples throughout this video all explained using clear and easy to understand language.