Talk:Pedal curve

Latest comment: 2 years ago by 203.13.3.94 in topic A little history would be nice

Epicycloids

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Hm. Contrary to its pedal curve page, this mathworld page says the epicycloid does not give a rose. But hypo and epicycloids are such close cousins they should both or neither. I'll check carefully. 142.177.20.80 01:08, 2 Aug 2004 (UTC)

The page is mistaken. Working in the complex plane and starting with   and   (epicycloids have  , hypocycloids  ) we get
 
 
 
 
and, finally, the pedal curve is
 
Noting   and letting  
 
which is obviously a rose. 142.177.126.230 16:25, 2 Aug 2004 (UTC)
Mathworld's been corrected =) 142.177.126.230 23:07, 5 Aug 2004 (UTC)

Contrapedals

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More work needed on contrapedal curve; mainly, what's done in higher spaces? While one could sensibly use the curvature vector, one could also use the perpendicular subspace...and somehow the latter is more appealing. Kwantus 18:53, 2 Aug 2004 (UTC)

Merge with Orthotomic

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The orthotomic is simply the pedal magnified by a factor of 2. The current orthotomic article is just a stub, so the merge should be easy and it seems silly (not to mention a content fork) to have two articles about essentially the same curve.--RDBury (talk) 23:09, 9 October 2009 (UTC)Reply

The merge is done.--RDBury (talk) 13:57, 12 October 2009 (UTC)Reply

A little history would be nice

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It would be nice to know why on earth this construction is a thing, and why it's called a "pedal" curve. Something to do with feet or walking? 203.13.3.94 (talk) 23:56, 30 August 2022 (UTC)Reply