# Directional Derivative

- Author:
- Alfredo Sánchez Alberca

- Topic:
- Derivative

This applet illustrates the concept of directional derivative.

- Set the coordinates of point
with the X and Y sliders. - Set the direction of the unit vector
with the Angle slider. - Observe the curve that results from the intersection of the surface of the function with the vertical plane corresponding to
. - The directional derivative of the function
at the point along the direction of the vector is the slope of the tangent line to the previous curve at .

Get more info about directional derivatives at http://aprendeconalf.es.