# Evaluate and integrate equations

Grapher’s Equation menu includes functions for evaluating equations and performing integrations.

## Evaluate an equation at a specific point

Select an equation, then choose Equation > Evaluation.

In the Evaluation window, enter the point to evaluate in the Input field (3D graphs have two input fields), then press Return.

Automatically calculated values appear in the list below the Input field.

You can do any of the following:

*View related equations on the graph:*Select equations listed under Display.*Change the color of related equations:*Click the color well next to the equation.*Add selected related equations to the graph:*Click Stroke.

## Compute integral values

Select an equation, then choose Equation > Integration.

In the Integration window, do any of the following:

*Choose what to calculate:*Click the Integrate pop-up menu, then choose an option.*Enter bounds:*Enter values in the fields above and below the integral sign.*Set a bound to infinity:*Click the pop-up menu next to the integral sign (3D graphs have pop-up menus for each integral sign).*Change the method used to calculate the value:*Click the disclosure triangle next to Method, click the pop-up menu, then choose a method. You can change the default values for any of the methods.*Calculate the integral:*Click Calculate. This highlights the equation’s area or surface on the graph.*Remove highlighting:*Close the Integration window, then choose Equation > Remove Integrated Area.

**See also**Create a graph and add equations