3. Consider the utility function u(x, y) = ( 1 ) x+2y+1 (a) Find the equation for the marginal utility for x and one for marginal utility of y. (b) Find an equation of the form 3/ = f (x) that describes the indifference curve for utility equal to -l/2. (c) Argue that the utility values all lie in the interval [1,0] (d) Does the utility function 17(x, y) = x + 2y represent the same preferences as 1106. y)? (e) Does the utility function w(x, y) = x + 3! represent the same preferences as u(x.y)