Polynomial roots

In mathematics, a zero, also sometimes called a root, of a real-, complex- or generally vector-valued function ${\displaystyle f}$ is a member ${\displaystyle x}$ of the domain of ${\displaystyle f}$ such that ${\displaystyle f(x)}$ vanishes at ${\displaystyle x}$; that is, ${\displaystyle x}$ is a solution of the equation ${\displaystyle f(x)=0}$. In other words, a "zero" of a function is an input value that produces an output of ${\displaystyle 0}$.

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