Rationalising The Denominator | Algebra | Maths | FuseSchool

Click here to see more videos: https://alugha.com/FuseSchool In this video we discover what rationalising the denominator is and how to do it. The denominator is the bottom part of a fraction. Rationalising the denominator is when we move a root from the bottom - the denominator - to the top (the numerator). For a surd to be in it’s simplest form, the denominator cannot be irrational. We cannot have a root in the denominator. It isn’t wrong to have a root at the bottom - it just isn’t considered the simplest form. To move a root from the denominator, we need to multiply the top and bottom both by the root. Sometimes there is more than just a root in the denominator. When this happens, we need to multiply by the WHOLE of the denominator but change the sign. So if it was root 2 plus 3 then we need to multiply both the numerator and the denominator by root 2 MINUS 3. Our teachers and animators come together to make fun & easy-to-understand videos in Chemistry, Biology, Physics, Maths & ICT. VISIT us at www.fuseschool.org, where all of our videos are carefully organised into topics and specific orders, and to see what else we have on offer. Comment, like and share with other learners. You can both ask and answer questions, and teachers will get back to you. These videos can be used in a flipped classroom model or as a revision aid. Twitter: https://twitter.com/fuseSchool This Open Educational Resource is free of charge, under a Creative Commons License: Attribution-NonCommercial CC BY-NC ( View License Deed: http://creativecommons.org/licenses/by-nc/4.0/ ). You are allowed to download the video for nonprofit, educational use. If you would like to modify the video, please contact us: info@fuseschool.org

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