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## #1 2010-07-31 13:07:56

bossk171
Power Member

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### catenary

A catenary is the curve:

If you roll a parabola along the x-axis, the focus of the rolling parabola traces out a catenary. I read this a number of places, but I've yet been able to find, or create, a proof.

Last edited by bossk171 (2010-07-31 13:08:18)

There are 10 types of people in the world, those who understand binary, those who don't, and those who can use induction.

## #2 2010-07-31 14:16:34

bobbym

Online

### Re: catenary

In mathematics, you don't understand things. You just get used to them.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.

## #3 2010-07-31 15:39:45

bobbym

Online

### Re: catenary

Hi;

This page here gives the differential equation for the all the conic sections, yours is on the bottom. The differential equation can used to derive the curve as the focus of the parabola rides on the x axis, it will be found to be a catenary. This derivation is a proof.

In mathematics, you don't understand things. You just get used to them.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.

## #4 2011-07-27 15:39:17

Member

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### Re: catenary

Is the shape of the streamlines formed by a swimming duck a catenary? Is the shape of a supposedly shatterproof (I have broken them) ruler being bent, each end pressed onto my fingertips, a catenary? I know that the shape of a chain held at both ends is a catenary.

## #5 2011-07-27 19:36:52

anonimnystefy
Real Member

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### Re: catenary

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón