Réponses

2014-10-27T10:44:45+01:00
1.(2x+5)(x-1-2x+3)
=(2x+5)(-x+2)

2.(3x+1)(x-4-x-2)
(3x+1)(8)
=8(3x+1)

3.(2x+1)(2x+1-x-2)
=(2x+1)(x-1)

4.(2x+3)carré
  • Utilisateur Brainly
2014-10-27T11:00:28+01:00
(x - 1)(2x + 5) + (- 2x + 3)(2x + 5)
= (2x + 5)(x - 1 - 2x + 3)
= (2x + 5)(- x + 2)

(x + 4)(3x + 1) - (3x + 1)(x + 2)
= (3x + 1)(x + 4 - x - 2)
= 2(3x + 1)

= (2x + 1)² - (2x + 1)(x + 2)
= (2x + 1)(2x + 1 - x - 2)
= (2x + 1)(x - 1)

4x² + 12x + 9
= 2x * 2x + 2 * 2x * 3 + 3 * 3
= (2x + 3)²