Решите неравенство f039;(x)amp;lt;0, если f(x)=3x^4-4x^3-12x^2+3

F(x) = 3x - 4x - 12x + 3
f '(x) = 3(x)' - 4(x)' - 12(x)' + 3' = 12x - 12x - 24x

f '(x) lt; 0
12x - 12x - 24x lt; 0
x - x - 2x lt; 0
x(x - x - 2) lt; 0
x(x - 2)(x + 1) lt; 0
          -                        +                 -                      +

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                       - 1                      0                    2


x (- ; - 1) (0 ; 2)