Bonjour
A = 1/2 (1/4+1/5+5) = 1/2 ( 5/20+4/20+100/20) = 1/2 x 109/20 = 109/40
B = 9V7 -2V28 -5/3V63 = 9V7 -4V7 -15/3V7 = 27V7-12V7-15V7 = 0
C = 5V18 -6V32 = 5V2x3² -6V2x4² = 15V2 -24V2 = -9V2
D = (x-5)(2x+1) -2(x-1)(x+3) = (2x²+x-10x-5)-2(x²+3x-x-3) = 2x²-9x-5 -( 2x²+6x-2x+6)
= 2x²-9x-5-2x²-6x+2x+6 = -13x+1
E = 3(2-x)² -x (1-x)(2x+1) = 3(4-4x+x²) - x (2x+1-2x²-x) = 12-12x+12x²- (2x²+x-2x²-x²) = 12-12x+12x²-2x²-x+2x²+x²
= 13x²-13x+12
F = (3x-2)² -25x² = (3x-2-5x)(3x-2+5x) = (-2x-2)(8x-2)
G = (x-2)(x-2) -(4x-7) = (x-2)(x-2-4x+7) = (x-2)(-3x+5)
Pas certaine à 100% sur la B
