Réponses

2013-02-19T11:35:36+01:00

f(x) - (2x -3) = (-2x² +5x-2 + 2x² -2x + 3 - 3x )/(1-x) = 1/(1-x)

signe de f(x) - (2x - 3)

        x                                    1

1/(1-x)                   +               |            -

                   f(x) au dessus             f(x) en dessous

 

f(x) = x³ + x² + 1

t(h)  = (f(2+h) - f(2))/h = [((2+h)³ + (2+h)² + 1) - 13]/h = (h³ + 7h² + 4h)/h = h² + 7h + 4

f'(2) = lim       (h² + 7h + 4) = 4

           h->0