Réponses

  • Utilisateur Brainly
2013-12-24T18:45:45+01:00
I=(x+1)²+(2x-5)(2x+5)
=x²+2x+1+4x²-25
=5x²+2x-24

J=(3x-1)²-(3x-1)(2x-6)
=9x²-6x+1-(6x²-2x-18x+6)
=3x²+14x-5

K=(x+2)(x-2)-(2x-4)²+(2x+3)(1-7x)

=x²-4-(4x²-16x+16)-14x²+3-21x+2x
=-17x²-3x-17