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

Answered by Beth A. Maths tutor

4335 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

How to differentiate y=(x^2+4x)^5


The circle C has centre (2,1) and radius 10. The point A(10,7) lies on the circle. Find the equation of the tangent to C at A and give it in the form 0 =ay + bx + c.


What is integration?


How can functions be transformed?


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 2013–2024

Terms & Conditions|Privacy Policy