Prove: (1-cos(2A))/sin(2A) = tan(A)

Firstly we must lay out our double angle formulas which are required for this question: cos(2A) = 1-2sin^2(A) = 2cos^2(A)-1 sin(2A) = 2sin(A)cos(A) Working from LHS: (1-cos(2A))/sin(2A) Focusing on the denominator 1-cos(2A) = 1-(1-2sin^2(A)) = 2sin^2(A) Focusing on the numerator sin(2A) = 2sin(A)cos(A) Therefore, overall: (1-cos(2A))/sin(2A) = 2sin^2(A)/2sin(A)cos(A) = 2*sin(A)sin(A) / 2sin(A)*cos(A) = sin(A)/cos(A) = tan(A) AS REQUIRED 

RP
Answered by Rishi P. Maths tutor

20787 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

What is the point of differentiation?


What is the chain rule and how is it used?


(a) Express 9x+11/(2x+3)(x-1) as partial fractions and (b) find the integral of 9x+11/(2x+3)(x-1) with respect to x


Differentiate y = √(1 + 3x²) with respect to x


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