Let XXX have PDF f(x)=38(1−x2)f(x) = \frac{3}{8}(1-x^2)f(x)=83(1−x2) for ∣x∣≤1|x| \le 1∣x∣≤1. What is E[X]E[X]E[X]?
0
13\frac{1}{3}31
12\frac{1}{2}21
38\frac{3}{8}83