Sagot :
bonjour
A = (3x - 5)(x - 3)
=3x²-9x-5x+15
=3x²-14x+15
B = 2(3x - 1)(-x + 7)
=2(-3x²+21x+x-7)
=-6x²+42x+2x-14
=-6x²+44x-14
Bonjour,
A = (3x - 5)(x - 3)
double distributivité
3x*x = 3x²
3x* -3 = -9x
-5 * x = -5x
-5* -3 = 15
=> 3x² -9x -5x +15
= 3x² -14x +15
B = 2(3x - 1)(-x + 7)
simple distributivité , puis double distributivité
= (6x -2) ( -x +7)
= -6x² +42x +2x-14
= -6x² + 44x -14