Bonsoir,
H=4x²+9+12x
= (2x +3) ²
(a+b)²
J=(x+1)²-25=
( x+1-5) ( x+1+5) =
(x-4 ) ( x+6)
(a-b)(a+b) = a² -b²
L=(2x-1)²-(3x+2)²
(2x-1 -3x -2) ( 2x -1 +3x +2) =
(-x -3) (5x +1)
(a-b)(a+b) = a² -b²
K=(x+2)(3x-1)+(5x-4)(3x-1)=
on factorise:
(3x-1) ( x+2 +5x-4)=
(3x-1) ( 6x -2) =
16x² -6x -6x +2=
16x² -12x +2