- Calculus and Analysis
- Real Analysis
Directional Derivative and Tangent Vector
Give a simple proof or counterexample to disprove:
If tangent vector p E Rn is such that the directional derivative of f by k vanished for every function f then k =0.
If function f on Rn is such that the directional derivative of f by every tangent vector at every point vanishes, then f is constant.
The directional derivative of the product of two functions product of their directional derivatives.
Directional derivatives and tangent vectors are investigated.