Bonsoir,
Paris:
4x² +12x +9 + 14x² -4x +21x -6
= 18x² +29x +3
(2x+3) ( 2x+3 +7x-2)
= (2x+3) (9x +1)
4 *(-4)² +12*-4 +9 + 14*(-4)² -4x*-4+21*-4 -6
=4*16 - 48 +14 * 16 +16 -84 -6
= 64 -48+224 +16-84-6
= 166
Antilles:
16 -( 4x² +12x +9)
= 16 -4x² -12x -9
= -4x² -12x +16 -9
= -4x² -12x + 7
x=-1
16 -4(1) -12*-1 -9
= 16-4 +12 -9
= 15
(4-2x-3) ( 4 +2x+3)
identité remarquable
(-2x +1) ( 2x +7 )
