Welcome to Al Lehnen's Web Site

I am a mathematics instructor at Madison Area Technical College in Madison, Wisconsin USA. My address is 1701 Wright Street ;
Madison, WI 53704 ; Phone (608) 246-6567 ; Email alehnen@madisoncollege.edu
or aplehnen@execpc.com

The graphic above was generated as a parametric surface using the Java Program CalcPlot3D, authored by Professor Paul Seeburger of  Monroe Community College in Brighton, New York.

Biographical Information

Fall 2017 

Schedule of classes

The Axioms of Humility:
A. Just because I don't understand an idea, doesn’t mean that it is wrong.
B. Just because I do understand an idea, doesn’t mean that it is right.
       Solving the Cubic Equation an Excel file using Cardano's Method to find all roots of any cubic equation with real coefficients.