. . , ( 6.18). ( 6.18). ( ), , , .
, , . . -
, .
, . - . , . ( 6.19).
, , . . 1838 . , , , ( 6.20).
. .. .. . " ". . , , , , , ( 6.21).
"" . "" . .
, " ", 1944 . , . ( 6.22).
, :
D (demand curve for imperfcct competition)
(Herfindahl index)
LMC (long-run marginal cost curves)
(marginal cost) MR (marginal revenue) (price)
Q (quantity) , , (short-run marginal cost curves)