To graph an implicit function, first press the key and switch "Graph..." to "5: 3D."

Now, you can press and type the function. The equation shown at right is from Exercise 29 on p. 139 of the Larsen text. Note:

• You have to move all terms to the left side of the equation, so the equation (x² + y²)² = 4x²y must be converted to z1 = (x² + y²)² - 4x²y.
• Be careful that you put an explicit multiplication symbol between variables! If you type "xy", the calculator will interpret it as a single variable named "xy" - if you mean "x times y", type "x" "y."

Next, from the F1 window, select "9; Format."

From the "Style" menu, select "5: Implicit Plot."

Now, you can graph the function. Be warned, though - it takes a while! The calculator will keep you informed of progress as it calculates the plot. You can use the "F2 - Zoom" menu for standard zooming, and you can use the blue arrow keys to rotate the graph.