Réponse :
bonsoir
Explications étape par étape :
A = (x + 1) (x + 2) - 5 (x + 2)→ facteur commun (x + 2)
A = (x + 2) (x + 1 - 5)
A = (x + 2)( x - 4)
------------------------
B = (2x + 1)² + (2x + 1)(x + 3)
B = (2x + 1) (2x + 1) + (2x + 1) (x + 3) → (2x + 1) facteur commun
B = (2x + 1)(2x + 1 + x + 3)
B = (2x + 1)( 3x + 4)
-----------------------------
C = -5 (7x + 9) - (7x - 9) (7x + 9) → (7x + 9) facteur commun
C = ( 7x + 9)(- 5 - ( 7x - 9))
C = (7x + 9) ( - 5 - 7x + 9)
C = (7x + 9)( 4 - 7x)
----------------------------------
D = (9x + 3)(2x - 1) - (9x + 3)²
D = (9x + 3)( 2x - 1) - (9x + 3)(9x + 3) → (9x + 3) facteur commun
D = (9x + 3)( 2x - 1 - ( 9x + 3))
D = (9x + 3)( 2x - 1 - 9x - 3)
D = (9x + 3)( -7x - 4)
---------------------------------------
E = 5 ( 2x - 3) (4x + 3) + ( 2x - 3) ( 6x + 1)
→ (2x - 3) facteur commun
E = (2x - 3) ( 5×(4x + 3) + 6x + 1)
E = (2x - 3) ( 20x + 15 + 6x + 1)
E = (2x - 3) ( 26x + 16)
--------------------------------------------
F = (9x + 3) (2x - 1) - 9x - 3
F = (9x + 3) (2x - 1) - 1 ( 9x + 3)
→ (9x + 3) facteur commun
F = (9x + 3) (2x - 1 - 1)
F = (9x + 3) ( 2x - 2)
bonne soirée
