Max profit
MR = MC
substitution effect
Px/Py
effect of change in "relative price"
Profit
Tr-Tc
or
(mc)(q)-TC
or
q(p-ATC)
MPl
, change in Q / change in L
Marginal utility per dollar
Mu/p
Mu= change in U/ change in Q
P ( for natural)
MC, but MC<Atc
So P<ATC
Max Utility
MUx/Px = MUy/Py
ATC
TC/Q
or
AFC + ATC