Question

piecewise functions & Integration! Definite integral: f(x)dx pi to 0 when f(x) = sin(x), if x < pi/2 & cos(x), if x> or = to pi/2

Answer 1

Your stuff is not clear at all. May be write the question word for word.

Answer 2

\[\int\limits_{0}^{\pi/2}\] sin x. dx
= cos 0 - cos pi/2
1