joint density function

  1. S

    Marginal probability density and joint probability density functions

    Hi guys, if someone can help me with this homework i will aprecciated very much. I try to do the first one, but i only got de U=X and the V=X+Y. I have no idea of how to do the W=X+Y+Z, and therefore the points 2 and 3.
  2. V

    Joint Density Function From Given Correlation

    How do I find joint density function from a given correlation?
  3. A

    Joint Distribution

    Hi everyone, I've got a problem with a joint probability density function question. Given f(x, y) = e^-(x+y), 0 <= x < ∞ , 0 <= y < ∞ , and 0 otherwise I need to verify that f is a valid joint PDF. The fact that f(x, y) >= 0 for all x, y is obvious. However I'm having trouble with...