Vërteto identitetet e mëposhtme.

a) $\sec^{4}\theta - \tan^{4}\theta \equiv \sec^{2}\theta + \tan^{2}\theta$

b) $\cosec^{2}x - \sin^{2}x \equiv \cot^{2}x + \cos^{2}x$

c) $\sec^{2}A(\cot^{2}A - \cos^{2}A) \equiv \cot^{2}A$

d) $1 - \cos^{2}\theta \equiv (\sec^{2}\theta - 1)(1 - \sin^{2}\theta)$

e) $\frac{1 - \tan^{2}A}{1 + \tan^{2}A} \equiv 1 - 2\sin^{2}A$

f) $\sec^{2}\theta + \cosec^{2}\theta \equiv \sec^{2}\theta\cosec^{2}\theta$

g) $\cosec A\sec^{2}A \equiv \cosec A + \tan A\sec A$

h) $(\sec\theta - \sin\theta)(\sec\theta + \sin\theta) \equiv \tan^{2}\theta + \cos^{2}\theta$