math
Bilibili0:28Bilibili · Charles队长Original video
Calculus · 中文
Directional derivatives
A Chinese visual explanation of directional derivatives. Catalog metadata imported from the original Math Video site and checked against the source platform; not a transcript.
Reviewed learning material · Video analysis · English
This video demonstrates the geometric meaning of directional derivatives using a 3D animation. It shows a surface z=f(x,y) and constructs a secant line between two points separated by distance rho along a direction vector l. As rho approaches zero, the secant becomes a tangent line. The formula for the directional derivative is displayed as a limit, representing the slope of this white tangent line.
Before you watch
- Multivariable functions
- Limits
- Parametric equations of lines
