A random variable XXX has PDF f(x)=2(1−x)f(x) = 2(1-x)f(x)=2(1−x) for 0≤x≤10 \le x \le 10≤x≤1. What is E[X]E[X]E[X]?
1/31/31/3
1/21/21/2
2/32/32/3
1/41/41/4