# Tangent plane and normal line to a surface

- Author:
- Alfredo Sánchez Alberca

This applet illustrates the computation of the normal line and the tangent plane to a surface at a point .

- Select the point
where to compute the normal line and the tangent plane to the graph of using the sliders. - Check the box Normal line to plot the normal line to the graph of
at the point , and to show its equation. - Check the box Tangent plane to plot the tangent plane to the graph of
at the point , and to show its equation. - Enter a new function and repeat the previous steps.

Get more info about the normal line and the tangent plane to a surface at http://aprendeconalf.es.