# What is a zero of a function?

##### 1 Answer

Jan 27, 2015

A zero of a function is an interception between the function itself and the X-axis.

The possibilities are:

- no zero (e.g.
#y=x^2+1# ) graph{x^2 +1 [-10, 10, -5, 5]} - one zero (e.g.
#y=x# ) graph{x [-10, 10, -5, 5]} - two or more zeros (e.g.
#y=x^2-1# ) graph{x^2-1 [-10, 10, -5, 5]} - infinite zeros (e.g.
#y=sinx# ) graph{sinx [-10, 10, -5, 5]}

To find the eventual zeros of a function it is necessary to solve the equation system between the equation of the function and the equation of the X-axis (