Question

cum se rezolva sistemul simetric x+y=1 xy=-6?

Answer 1

x+y=1 => x= 1-y
xy=-6

y(1-y)=-6 => -y^2+y+6=0 => -(y+2)(y-3)=0 => y=-2  si y=3

Daca y= 3 => x= -2
Daca y=-2 => x=3

S: { (-2,3); (3,-2) }