# Random variables (probability)

## Homework Statement

I have the joint cdf of two random variables X and Y and they ask me to find the cdf of just Y. I know that you just take the limit of the cdf as x->infinity, but I am just wondering if you can also do this by calculating the joint pdf and then the marginal of Y and then from the marginal of Y, the cdf of Y.

## The Attempt at a Solution

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## Homework Statement

I have the joint cdf of two random variables X and Y and they ask me to find the cdf of just Y. I know that you just take the limit of the cdf as x->infinity, but I am just wondering if you can also do this by calculating the joint pdf and then the marginal of Y and then from the marginal of Y, the cdf of Y.

## The Attempt at a Solution

Yes, sometimes that is how it must be done. However, in your case that would be doing it the hard way, since taking the ##x \to \infty## limit is easier.

Yes, sometimes that is how it must be done. However, in your case that would be doing it the hard way, since taking the ##x \to \infty## limit is easier.
Thank you!!!!, I was so worried about that one in the test.