A continuous random variable XXX has CDF F(x)=x24F(x) = \frac{x^2}{4}F(x)=4x2 for 0≤x≤20 \leq x \leq 20≤x≤2. What is f(x)f(x)f(x)?
f(x)=x4f(x) = \frac{x}{4}f(x)=4x
f(x)=x2f(x) = \frac{x}{2}f(x)=2x
f(x)=12f(x) = \frac{1}{2}f(x)=21
f(x)=xf(x) = xf(x)=x