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May 26th, 2013, 02:47 AM   #1
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probability of X and Y

The joint propability function of X and Y is given by .

So far I found .

I still need to find and . The answer should be and , respectively. But I do not see how to get there.

For the first I take the double integral over 2 with and . For the second I take boundaries and . The answer I get are 1 and 0.

Why is this wrong and how should it be done?
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May 26th, 2013, 03:02 AM   #2
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Re: probability of X and Y

Now I took . I made a graph of and took the boundaries and . That gave me , so the first one is solved
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May 26th, 2013, 03:13 AM   #3
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Re: probability of X and Y

And a sketch also did the work for the other question. I took and and that gave me indeed the right answer.

Sorry for bothering and thanks anyway!
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May 26th, 2013, 03:46 AM   #4
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Re: probability of X and Y

[color=#000000]It is much easier to make the probability computations using area computation.

[attachment=0:m6xn6toy]george.png[/attachment:m6xn6toy]






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May 26th, 2013, 04:03 AM   #5
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Re: probability of X and Y

The graph indeed makes it perfectly clear. I'll remember the tip for other questions/problems. Thanks a lot!
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