Sagot :
e = 9x²+12x +4 -(3x²+21x+2x+14)
= 9x²+12x+4-3x²-21x-2x-14
= 6x²-11x-10
factorisation
= (3x+2)(3x+2)-(x+7)
= (3x+2)(3x+2-x-7)
=(3x+2)(2x-5)
pour x = 1/2
E = 6*(1/2)² -11/2-10
= 6/4-22/4-40/4
= 56/4 = 14
e = 9x²+12x +4 -(3x²+21x+2x+14)
= 9x²+12x+4-3x²-21x-2x-14
= 6x²-11x-10
factorisation
= (3x+2)(3x+2)-(x+7)
= (3x+2)(3x+2-x-7)
=(3x+2)(2x-5)
pour x = 1/2
E = 6*(1/2)² -11/2-10
= 6/4-22/4-40/4
= 56/4 = 14