Let XXX have PDF f(x)=12sin(x)f(x) = \frac{1}{2} \sin(x)f(x)=21sin(x) for 0≤x≤π0 \le x \le \pi0≤x≤π. What is E[X]E[X]E[X]?
\pi/4
\pi/2
\pi
0