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

6039 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Find the stationary point on the line of y = 6x - x^2 and state whether this point is a maximum or a minimum


How to differentiate using the Product Rule


What is the difference between differentiation and integration, and why do we need Calculus at all?


given y = x^2 - 7x + 5, find dy/dx from first principles


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning