e= (3x+2)°-(3x+2)(x+7) a; developper et reduire e b;factoriser e c; calculer e pour x=1/2 pouver vous m'aider svp

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