So you can imagine, both of these guys have distributions like this, and they're independent. So to get to sample q2, you essentially sample x1 from this distribution, square that value, sample x2 from the same distribution essentially, square that value, and then add the two, and you're going to get q2. This over here, we would write, so this is q1. q2 here is a chi-squared distributed random variable with two degrees of freedom. And just to visualize the set of chi-squared distributions, let's look at this over here. So I got this off of Wikipedia. This shows us some of the probability density functions for some of the chi-squared distributions.