Zero of a Function

• A zero (or root) of a function $f(x)$ is an element $c\in \text{dom}(f)$ such that $f(c)=0$.
• The zero set of a function $f(x)$ is the set of all zeros of $f(x)$
  • Remarks:
    • The zero of a function $f(x)$ can be viewed as the solution set of the equation $f(x)=0$.
    • The zero set of a linear map is also known as its kernel.