Réponses

Meilleure réponse !
2013-10-21T17:10:57+02:00
A = (y+8)²
   =y²+16y+64
B = (3y-9)²
   =9y²-54y+81
C = (y+7)(y-7)
   = y²-7y+7y-49
   = y²-49
D = (4y-5)(4y+5)
   = 16y²+20y-20y-25
   = 16y²-25
E = (2y-5)²-(4y+1)²
   = (4y²-20y+25)-(16y²+8y+1)
   = 4y²-20y+25-16y²-8y-1
   = -12y²-28y+24