x2−2x+2=0x^{2}-2 x+2=0x2−2x+2=0
x2+2x−2=0x^{2}+2 x-2=0x2+2x−2=0
x2−2x−2=0x^{2}-2 x-2=0x2−2x−2=0
x2+2x+2=0x^{2}+2 x+2=0x2+2x+2=0