2 Développe puis réduis chaque expression. C = (2x + 5)(3x + 7) C - 2x x .... + 2x x... + 5 x...... + 5 x C= C= D = (x + 1)(x + 5) E = (4x + 5)(2x + 6) F = (2 +

Réponse:

C = 6x²+29x+35

D = x²+6x+5

E = 8x²+34x+11

F = 5x²+14x+8

Explications étape par étape:

C = (2x+5)(3x+7)

C = 2x×3x+2x×7+5×3x+5×7

C = 6x²+14x+15x+35

C = 6x²+29x+35

D = (x+1)(x+5)

D = x×x+x×5+1×x+1×5

D = x²+5x+x+5

D = x²+6x+5

E = (4x+5)(2x+6)

E = 4x×2x+4x×6+5×2x+5×6

E = 8x²+24x+10x+11

E = 8x²+34x+11

F = (2+x)(5x+4)

F = 2×5x+2×4+x×5x+x×4

F = 10x+8+5x²+4x

F = 5x²+14x+8