10-22. Let {X1,X2, . . . ,Xn} be a set of sample random variables for each of the following probability density functions. Find a sufficient statistic forθ > 0:

(a) f (x; θ) = 2θ

−2x, 0 < x < θ

(b) f (x; θ) = θxθ−1, 0 < x < 1, θ > 0