Réponses

2013-03-06T10:21:14+01:00

E = 16 - (5x - 3) ²

E = 16 - 5x² - 2x 5x x 3 + 9

E = 16 - (25x² - 30x + 9) 

E = 7 - 25x² +30x

E = - 25x² +30x + 7

 

E = 4 x 4 - (5x - 3) (5x - 3)c'est la forme a² - b²

donc tu factorises en developpant ( a-b) (a+ b)

E = ((4 - 5x - 3) (4 + 5x - 3)

E = (1 - 5x) (1 + 5x)°