Suppose we are given that the value of a particular utility function is a constant.That is,U(X,Y)= c.Then,the total derivative of this relation is:
A) (  U/  X)dX + (  U/  Y)dY = c.
B) (  U/  X)dX + (  U/  Y)dY = 0.
C) (  Y/  X)dX + (  X/  Y)dY = 0.
D) (  Y/  X)dU + (  X/  Y)dU = c.

Question

Quizplus · Accepted Answer

Total derivative of the given utility function is as follows:
dU = (F1F1F1S1U/F1F1F1S1X)dX + (F1F1F1S1U/F1F1F1S1Y)dY
Given U(X,Y) = c, so dU/dX = dU/dY = 0.
Therefore,
(F1F1F1S1U/F1F1F1S1X)dX + (F1F1F1S1U/F1F1F1S1Y)dY = 0.

Suppose We Are Given That the Value of a Particular