When doing mathematics, wouldn't it be nice if we could type an
equation into a cell in Excel and immediately see the resulting graph?

This article describes how this can be achieved by using just 4 input
cells and a set of defined names.
Content:
-
Introduction
-
Create the Chart
-
x-values
-
y-values
-
Sample Equations
Turns out this trick has been demonstrated before: Stephen Bullen has
created an almost
identical version of this workbook a long time ago, probably using
Excel 5. Look for a download called
ChtFrmla.zip.