See Hint Let u = f(1, x2) be a utility function, and let f(u) be a transformation of the utility function. Which of the following transformations are positive monotonic transformations of u? Choose one or more: O f(u) = 3u O f(u) = 100 - u O f ( u ) = 3 Of(u) = u+1 O f(u) = > 0 f (u ) = u3 Of(u) = u2 o f(u) = u - 200