bonjour,
ds l'ordre
2x(4x²+x-2)
3(x+1)+(x+1)² =
(x+1)(3+x+1) =
(x+1)(x+4)
x²-4+2x²+8x+8 =
x²-4+2(x²+4x+4)=
x²-4+2(x+2)² =
(x-2)(x+2)+2(x+2)²=
(x+2)(x-2+2x+4)=
(x+2)(3x+2)
18-8x² =
2(9-4x²) =
2(3-2x)(3+2x)
x²-6x+9 =
(x-3)²
4x²-(3x+2)²=
(2x-2x-2)(2x+3x+2) =
-2(5x+2)
(2x+3)²-4 =
(2x+3-2)(2x+3+2)=
(2x+1)(2x+5)