Evaluate:
(i) `int(tanx+cotx)^2\ dx`
(ii) `int(1-cos2x)/(1+cos2x)\ dx`

Explanation

(i) `int(tanx+cotx)^2\ dx`


`=int(tan^2x+cot^2x+2)\dx`


`=int(sec^2x-1+cosec^2x-1+2)\dx`


`=tanx-cotx+C`



(ii) `int(1-cos2x)/(1+cos2x)\ dx`


`=int(2sin^2 x)/(2cos^2 x)\dx`


`=int tan^2 x\dx`


`=int (sec^2 x-1)\dx`


...