☺ Salut ☻
[tex]\rule{0.5cm}{1mm}DEVELOPPER\: ET\: REDUIRE\rule{0.5cm}{1mm}[/tex]
[tex]\boxed{B(x)=(x-1)(x+2)}[/tex]
[tex]\boxed{B(x)=x\times x + x\times 2 -1\times x -1\times 2}[/tex]
[tex]\boxed{B(x)=x^{2}+2x-x-2}[/tex]
[tex]\boxed{\boxed{\green{B(x)=x^{2}+x-2}}}[/tex]
[tex]\rule{6cm}{1mm}[/tex]
