x4+2x2+1x^{4}+2 x^{2}+1x4+2x2+1
x4−2x2+1x^{4}-2 x^{2}+1x4−2x2+1
x4−x2+1x^{4}-x^{2}+1x4−x2+1
x4−2x−3x^{4}-2 x-3x4−2x−3