Verified answer

Bonjour,

a) A = (x+2)(x-3)+(x-3) = x²-3x+2x-6+x-3 = x²-9

   B = (2x-3)² = 4x²-12x+9

b) si x=3

        A = (3+2)(3-3)+(3-3) = ) = 5(0)+0 = 0

   ou A = 3²-9 = 0

   si x = 0

   A = (0+2)(0-3)+(0-3) = (2)(-3)+(-3) = -6-3 = -9

ou A = 0²-9 = -9

c)  la 2e (x²-9) permet un calcul très rapide

d) si x = 1,5

   B = (2(1,5)-3)² = (3-3)² = 0

  si x = 0

   B = (2(0)-3)² = (-3)² = 9