Preferences and utility functions

if A>B and B>C then A>C

straight line, generally the slope is -1

a concave right angle, it usually utilizes the minimum function

a convex right angle

u(x,y)=V(x)+y=x , the v(x) could be a square root

u(x,y)=Ax^(a)y^(b)

convert into a ln(x) + b ln(y)

1.plug in original x values into utility function and solve for u(x1,x2)
2. plug in u(x1,x2) value from ^ and plug in the single value to solve for the missing var

1. derive the utility function in terms of x1 and x2 respectively to find MUx1 and MUx2
2. MRS = -(du/x1 (or x) / du/x2 (or y))