Réponses

Meilleure réponse !
2014-10-11T18:40:47+02:00
F(x)=(x+5)(x-1)=0

x+5 = 0      x-1 = 0
x = -5         x = 1

F(x)=x au carré +4x-5=-5
x² +4x -5 = -5
x² +4x -5+5 = 0
x² +4x = 0
x(x+4) = 0

x = 0              x+4 = 0
                      x = -4
2014-10-11T18:42:58+02:00
F(x)=(x+5)(x-1)=0
f(x)=x²-x+5x-5=0
f(x)=x²+4x-5=0
f(x)=x²+4x-5+5=0+5
f(x)=x²+4x-4x=5-4
f(x)=x²=1
f(x)=x=1