What is the Probability Density Function for a Uniform Distribution on a Disc?

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Homework Statement



\D = \{(x,y) \in \mathbb{R}^2 | x^2 + y^2 \leq 1\} i.e. a disc or radius 1.
Write down the pdf f_{xy} for a uniform distribution on the disc.

Homework Equations


The Attempt at a Solution



f_{xy} = \frac{(x^2 + y^2)}{\pi} \mbox{for} x^2 + y^2<br /> 0 \mbox{otherwise}
as the area of the disc \pi[\tex] and to make it uniform you divide by \pi[\tex] so the probability integrates to 1&lt;br /&gt; &lt;br /&gt; i apologise in advance for posting the same thing twice. i don&amp;#039;t know how to delete 1 of them
 
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how do you get that probabilty density function? as the dsitribution is uniform, i think the probabilty of finding x&y in any region should be proportional to its area

also in line you can use itex rather than tex, f_{xy} = and functions within use the \ back-slash whilst to close the tex use the / forward slash
 
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