Question 1013468
It is - cot (theta)
1-1/sin^2 theta=numerator.  That is (sin^2 theta-1)/sin^2.
1-sin^2 theta is cos^2 theta
-(sin^2 theta-1)=1-sin^2 theta.
Therefore -cos^2 theta/sin^2 theta is numerator
Divide by cos theta/sin theta.
That give -cos theta/sin theta=-cot theta.