I'm taking some time to review mathematical functions, as my Friendly Mathematicians remind me that sines, cosines, and tangents, along with their inverses, are functions. There are rather dry chapters on functions in my algebra books, but the bounteous Web is full of entertaining sites like this one which use colorful graphics and large type to explain the matter to high school youth as well as people like me. Functions are processes, rather than chunky little problems with answers. They eat domains and excrete ranges. Functions can also be stuffed into other functions, rather like those Russian dolls that fit into each other. In the center of the mathematical nesting function doll is that little variable placeholder "x."

Surfing math web sites is kind of like going to a casino; there are lots and lots of entertaining colorful animated moving things, but you don't win (or learn) much. The best math web sites I've visited have a modest amount of razzle dazzle but plenty of words, and series of well-laid-out problems with accessible solutions. One of the best of this type of site is S.O.S. Math (watch out for the intrusive ads) which is just about everything I could ask from a math help website, including sample exams to take. Looking through the "Precalculus II" exam on this site, I find that I would not be able to pass it at all. I don't know, or haven't reviewed recently, most of the material on this exam. (Sigh.) The more I attempt to go ahead, the more work is placed in my way. I get this Sisyphean feeling when I try to move ahead in mathematics or physics. Sisyphus is the mythical guy who was condemned to roll the rock up the hill forever, trying to set it on top, but it always fell back down just before he got it there. The graph of Sisyphus' rock looks kind of like… a sine curve.

Posted at 3:01 am | link