## Factorials? What are They? A Simple Kind of Mathematics Shorthand

What are factorials? A variable is a symbol, often written as a letter of the alphabet that stands for a number that can vary in value. For example, take your age. That varies every year, doesn’t it? This year your age may be, say 21. If so, in 365 days your age will be 22. Another 365 days after that and your age will be 23. Thus age is a function of time. For you, we can write right now: A = 21 If the number of years that pass equals n, then for next year, n = 1 and An = 21 + n So, A₀ = 21 + 0 = 21 A₁ = 21 + 1 = 22 A₂ = 21 + 2 = 23 A₃ = 21…

## Analytic Geometry: The Ellipse and the Circle

The circle is really a special type of ellipse. In analytic geometry, an ellipse is a mathematical equation that, when graphed, resembles an egg. An ellipse has two focal points. The distance apart between the two points is one way of describing a particular ellipse. If the two points come together the ellipses become a circle with the point at its center. The equation for an ellipse is, x2/a2 + y2/b2 = 1 In this equation, "a" and "b" are constants that determine the shape of the ellipse, whereas x and y are variables, i.e., they can take on a host of values. When the value for x is known, the value for y is determined. Or, if it is y that is known, then x is determined. If a…

## Algebra for Beginners: Student Perspective

Have you gone past arithmetic and tried algebra for beginners? Having opted for the “college prep program” at high school, I took Algebra I, freshman year. My instructor was Miss Diamond. She wore those black lace-up shoes elderly women wore then. She was not unkind, although she was rather out of touch with some of the students—including me. It was the first days of class, and, despite seeking her help, I wasn’t getting the concepts. So I turned to the student seated behind me. In about five minutes—perhaps less—he set me straight with his algebra for beginners. I became one of the best students in the class. The principles are easy. Constant -vs- Variable The simplest concept was also the most difficult for me, as paradoxical as that may sound.…