Simplify and Prove Identities (HSC SSCE Mathematics Advanced): Quizzes

$\cos^2\theta + \sin^2\theta = 1$

$1 + \tan^2\theta = \sec^2\theta$

$1 + \cot^2\theta = \cosec^2\theta$

Divide by $\cos^2\theta$

When $\cos \theta = 0$

The x-coordinate

The more complicated side

$\sec \theta = \frac{1}{\cos \theta}$

$\sec^2\theta$

When $\sin \theta = 0$