DEVELOPPE PUIS REDUIS x(x+1)(x-2)
x(x²-2x+x-2)
x3-2x²+x²-2x
x3-x²-2x
x(x+1)(x-2)=
(x²+x)(x-2)
x³-2X²+X²-2X
X³-X²-2X
