Sagot :
a) y^2-y+5y-10-6y-30
y^2-2y-40
b) (y+5)(y-2-6)
(Y+5)(y-8)
c) (y+5)(y-8)=0
donc
y+5=0
y=-5 ou alors
y-8=0
y=8
donc S{-5 ; 8 }
1a) A = (y+5)(y-2)-6(y+5)
A = y²+5y-2y-10-6y-30
A = y²-3y-40
b) A = (y+5)(y-2-6)
A = (y+5)(y-8)
c/ y+5 = 0 donc y = - 5
y-8 = 0 y = 8
donc la solution est y = -5 ou 8