Probability/Random variables question

ashah99
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Homework Statement
Finding the probability of randomly choosing a point within the unit square constrained within the quarter circle
Relevant Equations
P(( X, Y ) ∈ A) = ∫∫ fXY ( x, y )dxdy
Hello all, I am wondering if my approach is coreect for the following probability question? I believe the joint PDF would be 1 given that the point is chosen from the unit square. To me, this question can be reduced down to finding the area of 1/4 of a circle with radius 1. Any help is appreciated!
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It's clear from your calculations that you are indeed simply calculating the area. Which is what you would expect for a uniform distribution.
 
PeroK said:
It's clear from your calculations that you are indeed simply calculating the area. Which is what you would expect for a uniform distribution.
Ok, makes sense. Would you agree that my answer is correct? Just want to make sure I understand.
 
ashah99 said:
Ok, makes sense. Would you agree that my answer is correct? Just want to make sure I understand.
Yes, it's just a ratio of areas, as you've calculated.
 
Or use polar coordinates: <br /> \int_0^1 \int_0^{\sqrt{1-x^2}} 1\,dy\,dx = \int_0^{\pi/2}\int_0^1 r\,dr\,d\theta.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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