Let the probability density of the random variable X be f (x) = e ^ - x, X > 0,0, other, find the probability density function of y = e ^ X Ask for detailed explanation

Let the probability density of the random variable X be f (x) = e ^ - x, X > 0,0, other, find the probability density function of y = e ^ X Ask for detailed explanation

F(y)=P(Y,=y)=P(e^x