RE: Definition of Derivative for Vector Functions

The GeoGebra part around 7:17 made the limiting idea cilck for me, the secant settling into the tangent was great,!
Framing the tangent as the secant scaled by 1 over h as h shrinks ties things back to the standard derivative and and keeps the intuition clean.
The quick note on the unit tangent as the normalized derivative is handy, my brain did a happy dance.

!HUG