- instantaneous rate of change
- Discworld (allthetropes.org)
The Discworld, a flat planet carried by four elephants standing on the back of a gigantic space-turtle, is the venue for Sir Terry Pratchett’s long running fantasy series.
- Derivative (Wikipedia)
In mathematics, the derivative shows the sensitivity of change of a function’s output with respect to the input. Derivatives are a fundamental tool of calculus. For example, the derivative of the position of a moving object with respect to time is the object’s velocity: this measures how quickly the position of the object changes when time advances.
