The x-intercepts (also called roots or zeros) of a given function f(x) are the points that the graph of the function crosses (or touches) the x-axis. The graphing calculator finds the x-intercepts by solving the one-variable equation f(x) = 0 on a specified interval.

In most cases, the x-intercept calculator finds all the x-intercepts on the interval efficiently. In some cases, some roots may not be detected. This often might happen when the graph of the function touches the x-axis without crossing it, for example, sin(x)2. In those cases, try again but set the decimal places to 16.

There are also cases where extraneous x-intercepts appear because of rounding off in function values. This can happen when the graph of a function is very close to the x-axis on a sub-interval. For example, the graph of x200 is very close to the x-axis on a sub-interval about 0 which produces unwanted x-intercepts or roots. In those cases, try again but set the decimal places to 0.

It is always helpful to look at the graphs when finding the x-intercepts of functions. If some zeros are missed or extra zeros appear, try solving again by changing the decimal places as explained above.

Also, note that there can always be functions for which none of their roots are detected. In those cases, try Shifting the left endpoint of the domain.