Question

Prove the identity:

Answer 1

\[\tan^2\theta-\sin^2\theta=\tan^2 \sin^2 \theta \]

Answer 2

\[Tan^2\theta=Sin^2\theta/Cos^2\]
\[Sin^2\theta/Cos^2-Sin^2\theta\]
\[\sin ^2\theta-Cos^2\theta*Sin^2\theta/Cos^2\]
\[Take the Sin^2\theta as Common factor\]
\[Sin^2\theta(1-Cos^2\theta/Cos^2)\]
\[ Sin^2 \theta*Sin^2\theta/Cos^2\]
\[Tan^2\theta*Sin^2\theta \]

Answer 3

Thanks!

Answer 4

Your welcome :)

Answer 5

I see that it's just mostly algebraic work, besides memorizing and applying the right identities. Hopefully I can do the rest of my problem sheet :)

Answer 6

Good to hear that @casualstudent