# Precalculus Project decision

OK so I have to do a research paper/presentation on an experiment/project that relates to my precalculus class. Only problem is that I was given no topics to choose from and I couldn't find any real good ones online. Can anybody give me some good ideas/topics that I can do? (P.S. if its fun then that's a plus :D)

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I want some ideas/topics for my precalc project but I have no leads as to what to pic so im asking you fellow math braniacs if you have any ideas that i can research/experiment on – Ronnie.j Sep 14 '11 at 1:27
I'm sorry, I didn't mean to be unclear. I'm not certain if this question belongs on this site - that's what I was getting at. I answered your question (although I don't know if it fits). In general, I like the idea that you ask a question in the best place for it to be answered, but questions like this are likely best for your teacher. We don't know what happens in your class or the scope of the task. But perhaps you'll strike it rich here. – mixedmath Sep 14 '11 at 1:29
oh i just need any ideas related to math basically, said my teacher lol – Ronnie.j Sep 14 '11 at 1:37
is there any way to make this question "big" so that i might get many ideas? – Ronnie.j Sep 14 '11 at 1:38
Ronnie.j, I think this is a nice question, give it some time and it may indeed get big. – Dan Brumleve Sep 14 '11 at 4:20

I have no idea what does or does not relate to your precalc class. But I hope that the construction of 3d figures as stacked 2d images fits, because I think it's very beautiful.

For instance, .

Depending on the things that you do in your class, these shapes might be different. But I think they're beautiful and fun. If you're very careful, you can even approximate certain volumes by adding up the weights of the pieces of paper (or whatever material), which suggests some deep things in math. Like calculus, in a way.

Or perhaps I'm completely off mark - just an idea.

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Thanks, i jst need any idea that relates to precal/calculus – Ronnie.j Sep 14 '11 at 1:28
For a topic title, i would put 3D images on 2D pictures. Is there anyway you can like explain/evauluate on your topic? – Ronnie.j Sep 14 '11 at 1:43
as in what you are doing, i can tell that your shaping paper in different positions that by itself, looks 2 dimensional, but but together, looks 3 dimensional. I am very interested in your topic and would like to learn more about it – Ronnie.j Sep 14 '11 at 1:45
Incidentally, the equation on paper graph is incorrect. It should read $$z=\frac{\sin\sqrt{x^2+y^2}}{\sqrt{x^2+y^2}}.$$ – anon Sep 14 '11 at 8:23
I agree, it's beautiful! How do you get the edge marker to be a constant width? Do you cut first, or mark first? – TonyK Sep 14 '11 at 11:33

When i was given a similar choice, i chose this, seemed fun and also pretty useful

http://en.wikipedia.org/wiki/Inclinometer

will take some effort into building it, but is a good idea nevertheless

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so your idea is to build one? – Ronnie.j Sep 14 '11 at 1:38
ya, just make a wooden protractor (en.wikipedia.org/wiki/Protractor) and then what you do is, hand a thread at the 0 degrees point and then use it, if u r really interested in much more precision, you can even build a stand, i more of recommend en.wikipedia.org/wiki/File:Clinometerlow.jpg this. Because its easy to make and simple to use. My teachers appreciated it a lot. And mor eover the above ones in the inclinometer page of wiki will be costly in my opinion – Bhargav Sep 14 '11 at 1:45
haha thanks for the ideas, much appreciated :) – Ronnie.j Sep 14 '11 at 2:30

For some fun, how about jump rope, or if you can recruit a couple more partners, Double Dutch?

Use a camera to take some pictures of the activity, and print them out to analyze and include in your report. What is the shape of the image of the rope? Perhaps it resembles part of a sine wave, or a parabola. Try it with the rope in motion, and also just dangling from two hands. Does it matter what angle the photograph is taken from? Does the distance of the camera from the rope change anything? What functions you have learned about fit the image of the rope most accurately? Do certain functions fit better than others under different circumstances? Can your formulate a hypothesis explaining the results?

If you have a digital camera to bring to class, you can repeat the experiment while giving your report, and I imagine this would make for a lively demonstration.

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For "precalculus", this is a bit too much, but: the true equations for the curve of the jump rope aren't that simple. – J. M. Sep 14 '11 at 4:45
J.M., I believe precalculus includes trigonometry, conic sections, plotting functions and such, so there should be plenty of ideas for approximations in that curriculum. Also, you are spoiling the fun. :) – Dan Brumleve Sep 14 '11 at 4:48
I probably didn't express myself clearly. What I said is that what I linked to, regarding the actual equations for the jump rope curve, are a bit out of reach for precalculus, so at best, OP should be happy with approximations. Sorry for confusing you. – J. M. Sep 14 '11 at 4:50
I found a free link: ztolk.interestingnonetheless.net/skippingrope.pdf – Dan Brumleve Sep 14 '11 at 4:59