Understanding derivatives

[Guest]

I am having trouble understanding what exactly derivatives are. could some one help with like an example or something. i'm lost. i know it is the slope of the line tangent to the graph, but what exactly does that mean?

 

[flakine]

A measure of the rate of change, or slope of a function at or between points.

 

[DavW]

I find it easiest to thing in terms of Mechanics. The derivative of position is the rate of change of position, or velocity. The derivative of velocity is the rate of change of velocity, or acceleration.