Write (3 + 2√5)/(7 + 3√5) in the form a + b√5

First multiply top and bottom by conjugate of denominator, (7-3√5), and expand(3 + 2√5)(7 - 3√5)/(7 + 3√5)(7 - 3√5)(21 + 14√5 - 9√5 - 30)/(49 + 3√5 - 3√5 - 45)Simplify top and botton(-9 + 5√5)/4Write in requested form-9/4 + (5/4)√5

BA
Answered by Beth A. Maths tutor

5422 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Split 1/x^2-1 into partial fractions


Differentiate with respect to x: 3 sin^2 x + sec 2x


A) Differentiate ln(x) b) integrate ln(x)


Find the x values for stationary points in the curve y=3sin(2x) for 0<x<180


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