Key areas such as the "History section" have citations. In the long-term the paragraph starting "Uses of the Taylor series..." under the section Analytic function and the section called Taylor series as definitions may eventually require a citation as although this may be common knowledge to a person studying the topic, the common person may still benefit from being able to verify these claims should this article eventually be submitted for a WP:FA. (See WP:SCG)
It is broad in its coverage.
a (major aspects): b (focused):
I will assume that the Mathematics Wikiproject (or an Mathematics expert) can confirm that this article has all the major aspects.