### 11.1.15 Factoring xn in a polynomial

The factor_xn command factors the largest power of the variable out of a polynomial, writing it as the product of a monomial of largest degree and a rational function having a non-zero finite limit at infinity.

- factor_xn takes P, a polynomial.
- factor_xn(P) returns P written as the product of its monomial of largest degree with a rational function having a non-zero finite limit at infinity.

#### Example

factor_xn(-x^4+3)

x4 | ⎛ ⎝ | −1+3 x−4 | ⎞ ⎠