In mathematics, a zero of a real-, complex-, or generally vector-valued function f {\displaystyle f}, is a member x {\displaystyle x} of the domain of f {\displaystyle f} such that f {\displaystyle f} vanishes at x {\displaystyle x} ; that is, the function f {\displaystyle f} attains the value of 0 at x {\displaystyle x}, or equivalently, x {\displaystyle x} is the solution to the equation f = 0 {\displaystyle f=0}. Wikipedia