bonjour
A= x ²- 4x
A = x ( x - 4 )
B = 3x-9x ² = 3 x ( 1 - 3 x )
C= 4(x-3) +x ( x-3 ) = ( x - 3 ) ( 4 + x )
D = 4x ²-9 = ( 2 x - 3 ) ( 2 x + 3 )
E= 9x ²-12x + 4 = ( 3 x - 2 )²
F = ( 1-x) ( x+3 ) - ( x-1 ) ( 2+x )
= - ( - 1 + x ) ( x + 3 - 2 - x )
= - 1 ( - 1 + x )