Réponses

  • Utilisateur Brainly
2013-06-04T17:46:32+02:00

1) (3x-1)²-(x+5)²

9x² - 8x + 1 - x² + 25x + 25

8x² - 17x + 26

2013-06-04T17:48:01+02:00
1) (3x-1)^2-(x+5)^2=9x^2-6x+1-(x^2+10x+25)
=9x^2-6x+1-x^2-10x-25=8x^2-16x-24

2) 9x^2-18x=9x(x-2)