OCR, 2016, Higher Maths: Rationalise the denominator 1/(1+sqrt(3))

First make sure they know are clear on what a rational number isAsk them to try multiplying 1 + sqrt(3) by different values to see how to make it a rational numberE.g. they might try (1+sqrt(3))2 ---> see it doesn't work! We still have irrational numbers!Try (1+sqrt(3))(1-sqrt(3)) --> yes!! Middle terms cancel therefore we have a rational number!!Multiply both top and bottom of fraction by factor (1-sqrt(3)) to get answerTalk about theory; for any rationalisation question (a+b)(a-b) = a2+b2so if you see a square root at the bottom but squared number would be rational, use this. We call this the 'conjugate'. https://mrbartonmaths.com/resourcesnew/qotw/Badly%20Answered%20Booklets/badly-answered-1-higher-1.pdf

Answered by Garima A. Maths tutor

2591 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Yesterday it took 5 cleaners 4 and ½ hours to clean all the rooms in a hotel. There are only 3 cleaners to clean all the rooms in the hotel today. How much time will it take them?


Solve the simultaneous equations: y = x + 6, x^2 + 2y = 9


Expand the expression (3x+2)(3-2x)


Solve the equation:


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences