Bonjour
1)
P(x) = (x-1.6)(x²-3x+2) = x^3-3x²+2x-1.6x²+4.8x-3.2 = x^3-4.6x²+6.8x-3.2
2)
x²-3x+2=0
calcul du delta = b²-4ac = 9-4*2 = 1
deux solutions x' = (-b-Vdelta)/2a =(3-1)/2 = 1
x" = (-b+Vdelta)/2a =(3+1)/2 = 2
3)
rajout de la solution de x-1.6 = 0 alors x = 1.6
