OAF.FTPA
The Factor Theorem of Polynomial Algebra:
For any polynomial function,$P$,
$P(r) = 0$ if and only if $x -r$ is a factor of $P$. That is,
$P(r) = 0$ if and only if there is a polynomial $g_r$ where $P(x) = (x-r)*g_r(x)$
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