# Using precalculus to write a TI-84 program

I am in a precalculus class, and I am attempting to do a project on practical application.

The majority of students use the TI-84 for various math courses. They are also available in the library to rent. Unfortunately, few students take the time to actually use this wonderful tool. I would like to create a web-type video that can be posted on the course's forums, giving a demonstration on creating simple TI-84 programs that could be used to make life a little easier. Take a concept out of the book, and demonstrate the practical use.

Most of my hobby activity involves electronics of some sort. I have a bad habit of explaining things far too technically. I have difficulty explaining things in simple terms. My goal with this project is to learn how to explain concepts in terms others can understand, and possibly to help someone else learn.

After many scrapped ideas and half written programs, I was thinking of writing a simple program that calculated the maximum number of lightbulbs that could be safely connected to a 15 Amp breaker. I suppose it would be easy enough to allow the rating of the breaker to be a variable, but first things first. Don't want to get too advanced before I have a clear working model.

Can anyone suggest another role that functions play in our every day electrical/electronic life?

Many thanks.

What about demonstrating charge/discharge for capacitors? This could be defined as an exponential function in the form of

f(x) = (100.3140741)(0.6056796398)^x

where is restricted to [0,5] (due to there being only 5 charging cycles)

Obviously I have not completely worked through this, but that's the general idea. Capacitors may go beyond some of the students' understanding. But others may understand the concept. Some may become more interested. Either in capacitors or in the capability of practical usage of a TI84.

Thank you for all the ideas. I really wanted to stay with electronics as the basis, but if this does not work out, I may use some of these ideas.

[tangent] Man, talking about programming TI's takes me back. I wrote a ton of programs in in high school/college to handle the formals we used all the time, like the quadratic formulas. Although I probably spent more time drawing and programming animations. Drawing all the frames using the graphing tools wasted more class time then I'd like to admit. [/tangent]

I'm surprised teachers don't cover more of the calcs functions and how to use them. At the school i went to they had special teacher versions of the TI-82 that connected to a screen that went on an overhead projector so they could demonstrate the calc and its functions.

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