Factor theorem

In algebra, the factor theorem is a theorem linking factors and zeros of a polynomial. It is a special case of the polynomial remainder theorem.

The factor theorem states that a polynomial ${\displaystyle f(x)}$ has a factor ${\displaystyle (x-k)}$ if and only if ${\displaystyle f(k)=0}$ (i.e. ${\displaystyle k}$ is a root).

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