Répondre :
Bonjour;
a (2x+3)( 3x + 8);
=6x² +16x +9x +24
= 6x² +25x +24
2x x3x=2x3 xxxx = 6.x².
incompréhensible
c (7-4x)(6x - 5).
42x -35 -24x² +20x
= -24x² +62x -35
b (1+2x)(9x - 4);
= 9x -4 +18x² -8x
= 18x² +x -4
Bonjour;
a (2x+3)( 3x + 8);
=6x² +16x +9x +24
= 6x² +25x +24
2x x3x=2x3 xxxx = 6.x².
incompréhensible
c (7-4x)(6x - 5).
42x -35 -24x² +20x
= -24x² +62x -35
b (1+2x)(9x - 4);
= 9x -4 +18x² -8x
= 18x² +x -4