Computing Ordinary Demands a Cobb-Douglas Example Suppose that the consumer has Cobb-Douglas preferences U(XI, X2)=xix Then MU Ox,axd-xb U MU- OU Ox2bx月x21Computing Ordinary Demands - a Cobb-Douglas Example. Suppose that the consumer has Cobb-Douglas preferences. Then U x x x x a b ( , ) 1 2 = 1 2 MU U x ax x a b 1 1 1 1 = = 2  −  MU U x bx x a b 2 2 1 2 1 = =  − 