I have this homework question I'm not 100% sure how to tackle.
I have a random vector with joint distribution function F(x,y) and am asked to find the marginal distribution function.
I think need to get to $fx(x,y)$, but I'm not sure how to do this.
My thinking is that I need to differentiate F(x,y) by both x and y, to get f(x,y) and then integrate over y, but this gets me the marginal density for x.
Any pointers would be greatly appreciated
EDIT - Thanks Glen. I've switched to my proper user id. It's late here, I'll revisit tomorrow.
EDIT2 - to clarify, the first q in the homework starts at $F(x,y)$ and asks for marginal probability. The second starts with $f(x,y)$ and asks for marginal density so I'm assuming that in the first instance, they're after a pdf, and in the second, a cdf; to rule out suspicions of casual terminology use.