Réponses

2013-03-27T17:56:03+01:00

x²+x-6 = 6

x² + x  - 12 = 0 => (x + 4)(x - 3) = 0 => x = -4 ou x = 3

2013-03-27T17:59:58+01:00

f(x) = 6
x² +x -6 = 6 
x² +x -12 = 0
(x-3)(x+4) = 0
Donc x=3 ou x=-4.