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A Very Special Saturday

This Saturday…12/13/14…is a very special day. There won’t be another date like that (a sequential date) for another 89 years, which makes for a once in a lifetime opportunity to do something special.

Interestingly, the numbers 12, 13, and 14 involved in Saturday’s date are also related to each other in very special ways. I recently wrote about the neat connections in an article that went up on the Huffington Post. It’s a short, fun read, so check it out before you plan your special activities for Saturday.

Interactive Math: How Trigonometry Can Help You Get Better Sleep

Math is everywhere, even in your dreams! Okay, maybe not literally, but there is some truth to the statement.

During sleep our bodies cycle between different sleep stages, with one full cycle lasting on average 90 minutes. This periodic phenomena can be described by trigonometric functions. In my newest addition to the Interactive Math page I discuss the cosine function that describes a typical sleep cycle, and how you can personalize it to help you get better sleep. Check it out: Sleep Cycle Cosine Model.


Interactive Math: Calculus of Coffee Cooling and Secant Lines to Tangent Lines

New Additions to the Interactive Math Page

I’ve added two new links to the Interactive Math page:


  • Secant lines to tangent lines. Learn how secant lines (lines through two points on a graph) are used to introduce the derivative in calculus. You’ll get to interact with a graph and see how a tangent line (whose slope is the derivative) emerges by making the two points a secant line passes through closer together.



Both additions are related to content from my book, Everyday Calculus. Visit the Interactive Math page to find out more.