Réponses

2013-11-03T17:32:03+01:00
Développer et réduire :
A=(3x-5)(7x-4)
=21x²-12x-35x+20
=21x²-47x+20

B=2x²-5+4x(3-5)
=2x²-5+12x-20x
=2x²-8x-5

Factoriser:
D= (4x-5)(3x+6)+(4x-5)(8x-9)
=(4x-5)(3x+6+8x-9)
=(4x-5)(11x-3)

E=(3x-2)(5x-3)-(5x-3)(6x-7)
=(5x-3)(3x-2-6x+7)
=(5x-3)(-3x+5)
2013-11-03T17:33:49+01:00
A= 21x^2 - 12x- 35x +20
A= 21x^2 - 47x +20

B= 2x^2 -5+12x-20
B= 2x^2 + 12x -15

D= (4x-5)(3x+6+8x-9)
D= (4x-5)(11x+3)

E= (5x-3)(3x-2+6x-7)
E= (5x-3)(9x-9)