Merci d'avance. 

Merci d'avance.  1) Développer : A= (2x -1)² + (x +1 )² B= 2(1-x)(2x + 7 ) C= x+2(x - 5) +8 (3-2x) D=(x -1)(x+2) - (2x+5)² Bonsoir A= (2x -1)² + (x +1 )² A = (4x² -4x +1) + (x² +2x +1) A = 4x² -4 x+1 +x² +2x +1 A = 5x² -2x +2 B= 2(1-x)(2x + 7 ) B = (2 -2x)(2x+7) B = 4x +14 -4x -14x B = -14x +14 C= x+2(x - 5) +8 (3-2x) C = x + (2x-10) + (24 -16x) C = x +2x -10 +24 - 16x C = -13x +14 D=(x -1)(x+2) - (2x+5)² D = x² +2x -x -2 - (4x² +20x+25) D = x² +2x -x -2 -4x² -20x -25 D = -3x² -19x -27 1) Développer : A= (2x -1)² + (x +1 )² =4x²-4x+1+x²+2x+1 =5x²-2x+2 B= 2(1-x)(2x + 7 ) =2(2x+7-2x²-7x) =4x+14-4x²-14x =-4x²-10x+14 C= x+2(x - 5) +8 (3-2x) =x+2x-10+24-16x =-13x+14 D=(x -1)(x+2) - (2x+5)² =x²+2x-x-2-(4x²+20x+25) =x²+2x-x-2-4x²-20x-25 =-3x²-19x-27