Verify the Identity
$$\frac{\csc^2\theta-\cot^2\theta}{1-\sin^2\theta}=\sec^2\theta$$
Verify Trig Identity
$$\frac{\sin \theta}{1+\cos \theta}+ \frac {1+\cos \theta} {\sin \theta} =2 \csc \theta$$
Verify Trigonometric Identity
$$\frac{\sec\theta \sin\theta}{\tan\theta+\cot\theta} = \sin^2\theta$$