A consumer is willing to trade 4 units of x for 1 unit of y when she is consuming bundle (8,1). she is also willing to trade in 1 unit of x for 2 units of y when she is consuming bundle (4,4). She is indifferent between these two bundles. assuming that the Utility function is Cobb-Douglas of the form U(x,y)=X^(alpha) Y^(beta), where alpha and Beta are positive constants, what is the utility function of the consumer?