Thread: Joint Probability Function
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Old October 11th, 2008, 05:29 PM
Laurent Laurent is offline
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Originally Posted by brd_7 View Post
Thanks so much, Ok this is what i got...

E[X]^2 = (1/3 + y/2)^2 = y^2/4 + 2y/6 + 1/9
There's no y in the answer (what is y?). In order to find the average, you integrate y as well:
E[X]=\int_0^1\int_0^1 x(x+y)dx\,dy. The same for X^2.
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