# Thread: function of a random variable

1. ## function of a random variable

supose that the random variable X is uniformly distributed between x=-4 and x=2 Y=9-X^2
whats the Y probability distribution?

My main problem here are the bounds how do I set the bounds? I think I have two values for the distribution between y=5 and y=9, since I have to split it in two problems, one in which dy/dx is positive and other where it is negative, and whad do I do with the point where dy/dx =0?!

2. You need to figure out where this is a 2 to 1 mapping and where it's a 1 to 1 mapping.
You can use calc1 with the transformation from one density to the other,
but you need to draw the parabola
and figure out the various regions.