Question

how do i prove this trigonometric identity?

Answer 1

\(\large \frac{\sin 2\alpha}{\sin \alpha}-\frac{\cos 2\alpha}{\cos \alpha}\)

Answer 2

\(\sin 2 \alpha=2\sin \alpha\cos\alpha\)

Answer 3

still there ?

Answer 4

yes

Answer 5

and cos2 a = cos^2a - sin ^2 a