## The derivative of a function: definition and geometric interpretation

The derivative of a function is its instantaneous variation, i.e. the slope of the tangent to the graphical representation of the function at that point. 1. General idea: an instantaneous variation We
A finite set is a set that can be counted using the natural numbers $$1,\ldots,n$$ for a certain natural number $$n$$. But what is counting ? And then, what is