Lagrange Multiplier - 3-D Graph
This applet allows you to explore visually where an extreme value may be. It may strengthen your understanding of the method of Lagrange multipliers. You may rotate and zoom in/out the graph, and move the little ball on the surface along the blue space curve. (You may have to download the *.ggb file to your local machine and start GeoGebra to open it.)
Find the extrema of along the constraint curve .