Question

Question #739a4

Answer 1

`-1/2sin(2x) +C`

Explanation:

`int (1-cot^2x)/csc^2x dx = int (1-(cos^2x/sin^2x))/(1/sin^2x) dx`

`= int (sin^2x-cos^2x) dx`

`= int -cos(2x) dx`

Substitute `u = cos(2x)` to get

`= -1/2 sin(2x) +C`