How do I prove: [math]\frac{\tan A}{1-\cot A} +\frac{\cot A}{1-\tan A} = \sec A\csc A + 1[/math]?
How do I prove that [math]\frac{\cot^2(\frac{a}{2})-\cot^2(\frac{3a}{2})}{\cos^2(\frac{a}{2})\cos(a)(1+\cot^2(\frac{3a}{2}))}=8[/math]?