`int_(0)^(pi) 5(5-4cos theta)^(1//4)sin theta d theta`

Evaluate the following integrals by changing the limits of integration after suitable subsitutions: underset(0)overset(pi)int5(5-4cos theta)^(1//4) sin theta d theta

Evaluate int_(0)^(pi//2) cos theta tan ^(-1) ( sin theta)d theta .

Evaluate int_(0)^(pi//2) cos theta tan ^(-1) ( sin theta)d theta .

int_(0)^(pi//2) (cos theta)/(sqrt(4-sin^(2)theta))d theta is equal to