# Thread: Identitiy help urgently needed

1. ## Identitiy help urgently needed

Hi , I am having problems proving the identity

$tan^2x-sin^2x=tan^2xsin^2x$

Heres what I have done so far
[tex]
sin^2x - sin^2x(cos^2x)
cos^2x

2. Originally Posted by nightrider456
Hi , I am having problems proving the identity

$tan^2x-sin^2x=tan^2xsin^2x$

Heres what I have done so far
[tex]
sin^2x - sin^2x(cos^2x)
cos^2x
$\tan^2{x} - \sin^2{x} = \frac{\sin^2{x}}{\cos^2{x}} - \sin^2{x}$

$= \frac{\sin^2{x} - \sin^2{x}\cos^2{x}}{\cos^2{x}}$

$= \frac{\sin^2{x}(1 - \cos^2{x})}{\cos^2{x}}$

$= \frac{\sin^2{x}\sin^2{x}}{\cos^2{x}}$

$= \tan^2{x}\sin^2{x}$.