Bonjour,
1)
f(x)= x²+2x+1-x-1
f(x)= x²+x
g(x)= x²+4x+4-3x²+12-10x-20
g(x)= -2x²-6x-4
2)
f(x)= (x+1)(x+1-1)
f(x)= x(x+1)
g(x)= (x+2)²-3(x+2)(x-2)-10(x+2)
g(x)= (x+2)[(x+2)-3(x-2)-10]
g(x)= (x+2)(x+2-3x+6-10)
g(x)= (x+2)(-2x-2)
3)
f(x)= x(x+1)
f(x)=0
x(x+1)=0
x=0 ou x=-1
g(x)= (x+2)(-2x-2)
g(x)=0
(x+2)(-2x-2)=0
x=-2 ou x= -1
f(x)= g(x)
x²+x= -2x²-6x-4
x²+2x²+x+6x+4=0
3x²+7x+4=0
x1=-4/3 et x2 =-1
(x²+x ) / (-2x²-6x-4)=0
je te laisse faire cette partie
