What is a Derivative?
- Almost every function has a derivative.
- The derivative of a function shows the rate of change (gradient) at any point on the parent function.

- The limit way of finding the gradient is called the first principles of a derivative, and it is roughly the equivalent of:


The Derivative Function
- The derivative function, also called the gradient function, is a function that shows the gradient of its parent function at any point.

- The notation dy/dx comes from "the change in y over the change in x", which is the definition of a gradient.
- The variables y and x can be replaced with different variables, especially when using the real-life applications of derivatives.

Differentiability vs Continuity

Sources
https://www.youtube.com/watch?v=iYUIl_ix4ng
https://calcworkshop.com/application-derivatives/derivative-graph/