Μarginal Distributions of f(x,y)

f(x,y) = e^(-x), 0<=x<inf, 0<=y<=1

To find the marginal PDFs here is what I did so far:
Marginal Distribution of x:
f(x) = integral from 0 to 1, e^(-x)dy = ye^(-x)
after evaluating I got e^(-x)

Marginal Distribution of y:
f(y) = integral from 0 to inf, e^(-x) = -e^(-x)
after evaluating I got 1

Am I evaluating each one using the wrong boundaries?


Ambassador to the humans
No. Why do you think you did it wrong? It looks good to me. You just need to make sure to note what the support of your marginal distributions are.