Another possible answer is f(x)={8/x^3 if x is equal or greater than 2 and f(x)={0 otherwise

F(x) is the cumulative distribution function for a continuous random variable X. Find the probability density function f(x) associated with F(x). 4 x 2 if x > 2 F(x) = otherwise O 8 f ( x ) = x3 if 0 4