Bonjour,
A = 7x(2x – 3) + 4(2x – 3)
(2x-3) ( 7x +4)
C = (2x - 3)(2x + 4) - (2x - 3)(x – 5)
(2x-3) ( 2x+4 -x+5)= (2x-3) ( x +9)
E = (2x - 2)² – 1
(2x-2-1) ( 2x-2 +1) = (2x-3) ( 2x-1)
identité remarquable : a²-b²
G = 4x² – 9+ (2x − 3)(x – 5)
4x² -9 = ( 2x -3)( 2x+3)
(2x-3) ( 2x+3 +x-5) =
(2x-3) ( 3x -2)