How do you find a rate of change, in any context, and express it mathematically? You use differentiation. Tutorials in differentiating logs and exponentials, sines and cosines, and 3 key rules explained, providing excellent reference material for undergraduate study.
Differentiation by taking logarithms
The logarithm of a product is a sum, and so logarithms can be used to simplify certain functions for the purpose of differentiation. Video tutorial 19 mins.