homogeneous of degree zero if x(ap, aw)=x(p, w) for any p, w and a>0 This property follows from the fact that choice is only a function of the budget set and Bow={x∈界:p·x≤w} is the same set as Ban. aw={x∈界:ap·x≤a} This fairly obvious claim is in many ways the underlying intellectual basis for the economic bias that the price level doesnt matter Differentiating x(ap, aw)=x(p, w)totally with respect to a gives us the following equationhomogeneous of degree zero if xp,w  xp,w for any p,w and   0. This property follows from the fact that choice is only a function of the budget set and Bp,w  x   L : p  x  w is the same set as Bp,w  x   L : p  x  w This fairly obvious claim is in many ways the underlying intellectual basis for the economic bias that the price level doesn’t matter. Differentiating xp,w  xp,w totally with respect to  gives us the following equation: