Evaluate the following:
$\frac{\cos 45^{\circ}}{\sec 30^{\circ}+\operatorname{cosec} 30^{\circ}}$
Evaluate:
$\frac{\tan 26^{\circ}}{\cot 64^{\circ}}$
$9 \sec ^{2} A-9 \tan ^{2} A=..........$
If $3 \cot A=4,$ check whether $\frac{1-\tan ^{2} A}{1+\tan ^{2} A}=\cos ^{2} A-\sin ^{2} A$ or not.
Evaluate:
$\frac{\sin 18^{\circ}}{\cos 72^{\circ}}$