(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Calculate the marginal density of fx (x).

Fx,y (x,y) = double integral of 4x.e^(x+y) when 0<x<y, 0 otherwise.

2. Relevant equations

3. The attempt at a solution

i set up the equation as fx (x) = integral from x up to infinity of 4x.e^(x+y) dy

i get 4x [e^(x+y)] from x to infinity,

thats when the problem arises as whatever i do there's always infinity in the question.

I'm told the answer is 4x.e^(-2x)

any help would be really appreciated.

thanks.

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# Homework Help: Marginal Density Fx (x)

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