Currently Being ModeratedMay 17, 2012 1:08 PM (in response to BBuchbinder)
The built-in facility in OS X is to use Grapher.app to write the equations and then Copy/Paste to Pages. While you are in Grapher you can see what the function would look like if you graphed it.
Currently Being ModeratedMay 19, 2012 6:34 AM (in response to BBuchbinder)
Sorry I did not see the word "Pages".
If so, the very best for iWork is MathType. You may download for 30 days trial, then it's MathType Lite for life if you don't by it.
What is very pleasant with Mathtype : after inserting a math expression in the Pages text, one click on it open the expression in MathType for modification, then quit mathType, check "Yes", the new expression is in your text.
Grapher.app does not allow that.