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Topic: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped

Replies: 27   Last Post: Oct 8, 2017 12:41 AM

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plutonium.archimedes@gmail.com

Posts: 17,520
Registered: 3/31/08
The butterfly cut, a V cut into conics Re: How we get a Ellipse from
a Conic

Posted: Oct 5, 2017 10:28 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On Thursday, October 5, 2017 at 8:59:20 PM UTC-5, Archimedes Plutonium wrote:
> On Thursday, October 5, 2017 at 4:55:17 PM UTC-5, qbwr...@gmail.com wrote:

>
> Well thanks for the thoughts, but I already proved several times over that a cone is always a Oval section unless of course your cut is a V shaped cut not a regular planar cut of /
>
> But if you can manufacture a nice parallelepiped out of pine wood of the size of a football for it is parallelepiped that have been my bugaboo throughout my life, would be of help. One with nice noticeable slanted angles on its sides.


Now, this V cut, let me call it the butterfly cut rather than the planar cut. For the butterfly cut seems to restore symmetry, and a butterfly is symmetrical on a axis.

But now, let us look at other figures rather than a cone and look at a tetrahedron and a square pyramid for both look like a cone adaption.

Now what happens with planar cuts in tetrahedron for they are triangles. Only a parallel to base cut is another equilateral triangle. But, if we make a V cut, a butterfly cut into the tetrahedron, then, unfold that cut on the dihedral angle, I sort of think we get a larger equilateral triangle if the cut is on the axis of the tetrahedron.

Now looking at the pyramid with a butterfly cut, and we get a rectangle.

So, this suggests that the butterfly cut into the cone can deliver also a circle as well as a ellipse.

AP


Date Subject Author
10/5/17
Read How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
plutonium.archimedes@gmail.com
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from Cylinder Sections-- knifes that are V and asymmetrical V shaped
Michael Moroney
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Jan Bielawski
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Dan Christensen
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Jan Bielawski
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Dan Christensen
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Me
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
qbwrfmlx@gmail.com
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Dan Christensen
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
plutonium.archimedes@gmail.com
10/5/17
Read The butterfly cut, a V cut into conics Re: How we get a Ellipse from
a Conic
plutonium.archimedes@gmail.com
10/6/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from Cylinder Sections-- knifes that are V and asymmetrical V shaped
Michael Moroney
10/6/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Jan Bielawski
10/6/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Jan Bielawski
10/6/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Me
10/6/17
Read 1)Gottingen's Dorothea Bahns, Laurent Bartholdi, are you as dumb
stupid and messy about Conics as Franz? Oval is the conic section, never ellipse
plutonium.archimedes@gmail.com
10/6/17
Read Re: 1)Gottingen's Dorothea Bahns, Laurent Bartholdi, are you as dumb
stupid and messy about Conics as Franz? Oval is the conic section, never ellipse
bursejan@gmail.com
10/6/17
Read 11) Is Andrew Wiles, John Conway failures of trigonometry like
Burse//sine wave is semicircle Not sinusoidal
plutonium.archimedes@gmail.com
10/6/17
Read Re: 11) Is Andrew Wiles, John Conway failures of trigonometry like
Burse//sine wave is semicircle Not sinusoidal
Jan Bielawski
10/7/17
Read Re: 11) Is Andrew Wiles, John Conway failures of trigonometry like Burse//sine wave is semicircle Not sinusoidal
Michael Moroney
10/7/17
Read 4) Harvard's Mark Kisin, Peter Kronheimer, Jacob Lurie as dumb as
Mike Moroney, still teaching a ellipse is a conic when even students know it
is a OVAL
plutonium.archimedes@gmail.com
10/7/17
Read Re: Archimedes "Always Wrong" Plutonium's descent into madness continues...
Michael Moroney
10/8/17
Read Re: 4) Harvard's Mark Kisin, Peter Kronheimer, Jacob Lurie as dumb as
Mike Moroney, still teaching a ellipse is a conic when even students know it
is a OVAL
Jan Bielawski
10/6/17
Read Re: 11) Is Andrew Wiles, John Conway failures of trigonometry like
Burse//sine wave is semicircle Not sinusoidal
Me
10/6/17
Read Re: 11) Is Andrew Wiles, John Conway failures of trigonometry like
Burse//sine wave is semicircle Not sinusoidal
qbwrfmlx@gmail.com
10/7/17
Read Re: 11) Is Andrew Wiles, John Conway failures of trigonometry like
Burse//sine wave is semicircle Not sinusoidal
Me
10/6/17
Read Re: 1)Gottingen's Dorothea Bahns, Laurent Bartholdi, are you as dumb
stupid and messy about Conics as Franz? Oval is the conic section, never ellipse
Me
10/5/17
Read Re: How we get a Ellipse from a Conic, and how we get a Oval from
Cylinder Sections-- knifes that are V and asymmetrical V shaped
Me

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