With reference to the two random variables of Exercise 7.5, show that if 1 = 2 = 1, the random variable Z = X1/X1 +

With reference to the two random variables of Exercise 7.5, show that if θ1 = θ2 = 1, the random variable Z = X1/X1 + X2 has the uniform density with α = 0 and β = 1.
Exercise 7.5
If X1 and X2 are independent random variables having exponential densities with the parameters θ1 and θ2, use the distribution function technique to find the probability density of Y = X1 + X2