Question

Verify the trig identity: 2cos^2(x/2)=(sin^2x)/(1-cosx)

Answer 1

Start with lefthandside:

2cos^2(x/2) = 1 + cos x = (1 + cosx)(1-cosx)/(1-cosx)
= (1 - cos^2x)/(1+cosx) = (sin^2 x)/(1-cosx)

Answer 2

thank you so much!

Answer 3

:)