Definition:Root of a Function
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Definition
Let $f: R \to R$ be a function on a ring $R$.
Let $x \in R$.
Then the values of $x$ for which $f \left({x}\right) = 0_R$ are known as the roots of the function $f$.
This is simply a generalization of the case where $f$ is a polynomial.
Zero of a Function
The field $K$ is usually the set of real numbers $\R$ or complex numbers $\C$.
In this case, for a given function $f$, the roots are often called the zeroes of the function $f$