Simplify: x5−xx3−x\frac{x^5 - x}{x^3 - x}x3−xx5−x
x2+1x^2 + 1x2+1
x2−1x^2 - 1x2−1
x2x^2x2
x4+x2+1x^4 + x^2 + 1x4+x2+1