Réponses

  • Utilisateur Brainly
2013-10-10T18:50:46+02:00
b(x)=(3x-1)(7x+2)-9x²+1
      =(3x-1)(7x+2)-(3x-1)(3x+1)
      =(3x-1)(7x+2-3x-1)
      =(3x-1)(4x+1)