Lecture 1: FUNCTIONS - Different kinds of numbers. - What is a function? - Sums and products of functions. - Composite functions (function of a function) - Inverse function. Share this:FacebookTwitterGooglePinterestLinkedInEmailTumblrPrint Leave a Comment Click here to cancel reply. Name * Email (will not be published) * Website Comment Notify me of follow-up comments by email. Notify me of new posts by email.