Infinite Geometric Series Through Philosophical Confusion

So, I stole a page from Benjamin Baxter’s playbook and taught a lesson with the aid of comments from the Internet.
Specifically, in Pre-Calculus I was teaching the formula for an infinite geometric sum:

so is the first term and r is the number a term is multiplied by to get the next term.
For example, take [...]

Junk Statistics Article

Something to look over with students: Recent article on bad statistics
The case echoes a similar statistical legend — the belief that to be healthy we should drink eight glasses of water a day. Last week, researchers at the University of Pennsylvania decided to search for the source of this statistic. Their conclusion: “It is unclear [...]

Forces on a Truss

(Today’s student guest is Erik Lundvall.)
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This problem pertains to construction and the way a given force acts upon a given structure. Trusses are triangular pieces used in the construction of some buildings to support weight of other objects such as the weight of the roof for example. In this particular problem the truss extends from [...]

Call of Duty 4, Meet Vectors

Today’s student guest blogger is Emilio Inocencio.
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One sunny afternoon after completing your homework, you decide to play your favorite video game Call of Duty 4. When you enter your room you find that someone has replaced your Xbox 360 with a machined labeled “Mega 64”. The contraption has a note attached that reads, “To Exit-say [...]

Trigonometry at High-Speed

Today’s student guest blogger is Adriana Garcia.
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My love for films has taken me to investigate more of the math involved when determining the camera shots needed in specific scenes. In a high-speed car scene, a certain camera angle is needed to fully portray the speed of the car while showing the audience the car going [...]

Student Guest Problems

I’m going to be posting (starting today) a series courtesy my Pre-Calculus students, who have written a number of trigonometry related problems. They’re not just equations with “solve for x”, but problems based on research of real life situations.
Feel free to make any comments you like and post solutions.

Carnival of Mathematics #30

So, I was first rather distressed when I found out I was doing Carnival #30; I thought, 30 isn’t that interesting a number, is it? But it turns out that:
1. 30 is the first number that’s a sum of four distinct nonzero squares, that is, . (Sequence)
2. 30 is the first Giuga number. (Sequence) It’s [...]

Carnival of Mathematics Deadline Looms

Next scheduled ¤ Apr 4, 2008
Host blog ¤ The Number Warrior
You can either send by the form or send directly to my email.
I’ll take anything before midnight Pacific time on April 3rd. If you send on the 4th I may still be able to slip you in but I cannot guarantee.