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### Probability density function - multivariate random variable

Hi experts!

I know that many of you are professional mathematicians. My question is about statcistics and sage:

given two independient random variables X and Y (with a probability density function fX and fY), and the multivariable random variable A defined by: A=h(X,Y),

How can I obtain the explicit equation of probability density function of random varible A?

I only know that the join probability density fuction fXY is fXY=fX*fY (because there are independent).

Thans a lot!!

### Probability density function - multivariate random variable

Hi experts!

I know that many of you are professional mathematicians. My question is about statcistics and sage:

given two independient random variables X and Y (with a probability density function fX and fY), and the multivariable random variable A defined by: A=h(X,Y),

How can I obtain the explicit equation of probability density function of random varible A?A?

I only know that the join probability density fuction fXY is fXY=fX*fY (because there are independent).

Like you can see in the article http://en.wikipedia.org/wiki/Probability_density_function section 'Multiple variables' we can write the pdf of A using Dirac delta function.