bonjour
A = (2x+3)² = 4x² + 3*2*2x + 9 = 4x² + 12x + 9
B = (5x-2)² = 25x² - 2*2*5x +4 = 25x² - 20x + 4
C = (4x-3)(4x+3) = 4x² - 9
D = (1+7x)² = 1 + 2*1*7x + 49x² = 1 + 14x + 49x²
E = (2-3x)² = 4 - 2*2*3x+9x² = 4-12x+9x²
F = (2x+7)²- (4x-5)² = 4x² + 28x + 49 - ( 16x² - 40x + 25) = 4x² + 28x + 49 - 16x² +40x - 25 = -12x² + 68x +24
bonne continuation ☺️