Our book does not define a monotonically increasing and decreasing function very well (see page 4).It is not clear, for instance, whether a constant function is increasing.
The Wikipedia entry for increasing function is a conventional way to resolve any ambiguity.
For instance, according to the Wikipedia definition, a constant function is both monotonically increasing and monotonically decreasing, but not strictly monotonically increasing or strictly monotonically decreasing.
The definition of monotonicity in our book appears to be equivalent (given the interpretation above!) to the definition of strict monotonicity
The details of the two examples done in class are here
These are supplementary notes focused on the math involved in the De L'Hopital Rule.
This is a comment in regard to one homework problem about illumination. The statement "Illumination is proportional to the cosine of an angle and inversely proportional to the square of the distance from the light source" results in the formula