5 A = (7 - 2x)(x + 1) B = (4x + 3)(4x + 3) C = (4x - 3)(4x - 3) D = (4x + 3)(4x - 3) Aidez moi svp

Réponse :

bonsoir

collège et non lycée merci

A =  7 x + 7 - 2 x² - 2 x  = - 2 x² + 5 x + 7

B =   16 x² + 12 x + 12 x + 9 = 16 x² + 24 x + 9

C =   16 x² - 12 x - 12 x + 9 = 16 x² -24 x + 9  

D =  16 x² - 9

a= (7-2x)(x+1)

 = (7x + 7 -2 x² -2x) = - 2 x² + 5 x + 7

b = (4x + 3)(4x + 3) = 16x² + 12x + 12 x + 9 = 16 x² + 24 x + 9

c = (4x -3 )(4x - 3) = 16 x² -12 x -12 x + 9 = 16 x² -24x +9

d= (4x+3 ) (4x -3) = 16 x² -12 x +12 x -9 = 16 x² -9