Adding Parametric Functions

Parametric graph. The x-axis is labeled "X" and goes from negative 1 to 1. The y-axis is labeled "Y" and goes from negative 1 to 1. The functions are defined as f(t) = t and g(t) = t<sup>3</sup>.

In parametric equations, x and y are both determined as a function of a third independent variable ( t ). For example, x = f(t)= 4 * cos(t) and y = g(t) = 4 * sin(t).

To add a parametric function to a Cartesian graph:

Insert a Cartesian graph or edit an existing graph by double-clicking it. The Cartesian Graph dialog box opens.
In the Layers section, click Add.
Select Parametric in the Add Cartesian Layer dialog box and then click OK.
Enter the function for x in f(t) = using t as the variable.
Enter the function for y in g(t) = using t as the variable.
Enter the Domain of the function. The default domain is from -20 to 20.
Select a Line Style for the line.
Select a Line Color.
If you want the layer to display only if a certain condition is met, enter an equation or a variable that evaluates to true or false into the Show if field. .

Note: When entering variables, enclose the variable name in two opening and two closing number signs (for example, ##var1## = 3). The variable you reference must be defined for the question or the preface associated with the question.
Click OK.