Cobb Douglas and Quasi linear

[Dilan]

What is unique about Cobb Douglas and Quasi linear functions? What does it mean to be unique?

[Taylor Stoltzfus]

Hey Dilan! 

What I give here is a short summary, since all of this information already exists in the utility funciton handout. The best thing you can do for your self is go check out the "Utility Function handout" since it covers this pretty well.

I couple of interesting points about Cobb-doug:

• It always has DMRS, so you can always use tangency (unlike quasi-linear, where it must be quasi-linear convex to use tangency)
• If you can get the exponenets to add up to one, it will tell you how much of your income you spend on each good (see utility function handout Problem #1a for the full explanation) 
• if U(x,y) =XY then Mux =Y. Very interesting that the Mux depends completely on how much Y you have in this case

A couple things about Quasi-Linear:

• Quasi-linear convex is similar to cobb-doug in that you use tangency
• Quasi-linear concave is totally different, and gives a boundary solution

As for what it means to be unique, that is a better question for your philosophy TA.