Show that sin2A is equal to 2sinAcosA

This question requires you to use the trigonometric identity sin(A+B)=sinAcosB + sinBcosA. The difficulty in this problem is noticing that you need to substitute 2A for A+A and then you can simply put this into the trig identity. Doing this leads to you sin2A=sinAcosA + sinAcosA which is 2sinAcosA.

SL
Answered by Samuel L. Maths tutor

36973 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

How do i solve differential equations?


Differentiate [ x.ln(x)] with respect to x


What is the sum of the first 10 terms of the geometric series 32 + 16 + 8 + ... ?


How do I find the solution of the simultaneous equations x+3y=7 and 5x+2y=8


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