. x f(x), f '(x) = 0, f (x) . , . .
. x - . f ' (x) x , x , - . , x .
. f(x)
f ' (x) x x. f ' (x) = 0, >0 ( <0), x () f(x). =0, , .
[a,b] y = f(x) , [a,b].
f(x) = 2x3 - 15x2+ 36x - 14.
. f '(x) = 6x2 - 30x +36 = 6(x -2)(x - 3), x1 = 2 x2 = 3. . x1 = 2 , . x2 = 3 , x2 = 3 .
x1 = 2 x2 = 3, : f(2) = 14 f(3) = 13.