Double Integral Help
I have a question in my Prob & Stat course that deals with double integration, and it's been two years since Calc III and I really don't remember exactly how to solve one. Here's the question:
The first part isn't really a double integral, but will eventually lead to one:
Integral ( xe^(-x(1+y) ) ) dy
Essentially, I am not sure how to integrate that for y. The bounds don't really matter in this case, I need to know the y-integration.
To anyone who can help, it'd be much appreciated. Thanks.
Your integral is:
Originally Posted by GmasterFlash13
Int(dxdy*xe^(-x-xy)) = Int(dx*xe^(-x) * Int(dy*e^(-xy)) )
where I have split the integral into components.
The second integral (the one you are interested in) can be simply done by assuming x is a constant (it doesn't vary as y varies anyway), so
Int(dy*e^(-xy)) = 1/(-x) * e^(-xy)
where I have neglected the integration constant.