x2−2x+1=0x^{2}-2 x+1=0x2−2x+1=0
x2−2x−1=0x^{2}-2 x-1=0x2−2x−1=0
x2−22x+1=0x^{2}-2 \sqrt{2} x+1=0x2−22x+1=0
x2−22x−1=0x^{2}-2 \sqrt{2} x-1=0x2−22x−1=0