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John Conway, David Riley,Gordon Sinnamon, Justin Trudeau,Christensen says why teach correct math-- ellipse is a cylinder section, never a conic section Re: John Horton Conway flunked

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  John Conway, David Riley,Gordon Sinnamon, Justin Trudeau,Christensen says why teach correct math-- ellipse is a cylinder section, never a conic section Re: John Horton Conway flunked Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-09-12 08:19 -0700
    Re: Archimedes "Total Failure" Plutonium flunked the Math Test of a lifetime-generation test moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-09-12 19:14 +0000

#423435 — John Conway, David Riley,Gordon Sinnamon, Justin Trudeau,Christensen says why teach correct math-- ellipse is a cylinder section, never a conic section Re: John Horton Conway flunked

On Wednesday, September 12, 2018 
Dan Christensen writes:
7:55 AM (1 hour ago) 
>WARNING TO STUDENTS:

AP writes: pretty stupid of John Conway to never admit the ellipse is never a conic, always a cylinder section, when even his students in class can prove it to John Conway by a cone, cylinder can and circle lid-- the asymmetry involved. Is this the modern day math class-- dictator math, not math of reasoning.

John Conway, David Riley,Gordon Sinnamon, Justin Trudeau,Christensen says why teach correct math-- ellipse is a cylinder section, never a conic section

Univ Western Ontario math dept 
Janusz Adamus, Tatyana  Barron,   Dan Christensen, Graham Denham, Ajneet Dhillon, Matthias  Franz, John Jardine, Massoud Khalkhali, Nicole Lemire, Jan Mináč, Victoria Olds, Martin Pinsonnault, Lex Renner, David Riley, Rasul Shafikov, Gordon Sinnamon 


Amit Chakma (chem engr) 

Univ. Western Ontario physics dept 
Pauline Barmby, Shantanu Basu, Peter Brown, Alex Buchel*, Jan Cami, Margret Campbell-Brown, Blaine Chronik, Robert Cockcroft, John R. de Bruyn, Colin Denniston, Giovanni Fanchini, Sarah Gallagher, Lyudmila Goncharova, Wayne Hocking, Martin Houde, Jeffrey L. Hutter, Carol Jones, Stan Metchev, Silvia Mittler, Els Peeters, Robert Sica, Aaron Sigut, Peter Simpson, Mahi Singh, Paul Wiegert, Eugene Wong, Martin Zinke-Allmang 

Univ Toronto, physics, Gordon F. West, Michael B. Walker, Henry M. Van Driel, David J. Rowe, John W. Moffat, John F. Martin, Robert K. Logan, Albert E. Litherland, Roland List, Philipp Kronberg, James King, Anthony W. Key, Bob Holdom, Ron M. Farquhar, R. Nigel Edwards, David J. Dunlop, James Drummond, Tom E. Drake, R.Fraser Code, Richard C. Bailey, Robin Armstrong 


Canadian Educ Ministers-- endorsing stalking hypocrites like Dan Christensen with his insane 2 OR 10 = 12 when even a Canadian 8 year old knows 2 AND 10 = 12. Endorsing the "perpetual stalking by Dan Christensen" 

Sebastien Proulx 
Jordan Brown 
David Eggen 
Gordon Wyant 
Zach Churchill 
Ian Wishart 
Rob Fleming 


   /\-------/\ 
   \::O:::O::/ 
  (::_  ^  _::) 
   \_`-----'_/ 
You mean the classroom is the world, not just my cubbyhole in Ontario? 
And, even though you-- professors of math who never want to fix and clean up error filled mathematics, your students deserve better, and you should quit teaching if you cannot come around to admitting a ellipse is a cylinder section, never a conic section. For it is embarrassing to have students smarter than the math professor who by taking a cone, cylinder can and a round lid, can prove on the spot, in the classroom that the cone yields an oval, never an ellipse. 

Proofs ellipse is never a conic, always a cylinder section by 
Archimedes Plutonium 
-------------------- 
Conics = oval, 2 proofs, synthetic, analytic 

Synthetic Geometry & Analytical Geometry Proofs that Conic section = 
Oval, never an ellipse-- World's first proofs thereof 
by Archimedes Plutonium 
_Synthetic Geometry proofs that Cylinder section= Ellipse// Conic section= Oval 

First Synthetic Geometry proofs, later the Analytic Geometry proofs. 

Alright I need to get this prepared for the MATH ARRAY of proofs, that 
the Ellipse is a Cylinder section, and that the Conic section is an 
oval, never an ellipse 

PROOF that Cylinder Section is an Ellipse, never a Oval:: 
I would have proven it by Symmetry. Where I indulge the reader to 
place a circle inside the cylinder and have it mounted on a swivel, a 
tiny rod fastened to the circle so that you can pivot and rotate the 
circle. Then my proof argument would be to say--when the circle plate 
is parallel with base, it is a circle but rotate it slightly in the 
cylinder and determine what figure is produced. When rotated at the 
diameter, the extra area added to the upper portion equals the extra 
area added to bottom portion in cylinder, symmetrical area added, 
hence a ellipse. QED 

Now for proof that the Conic section cannot be an ellipse but an oval, 
I again would apply the same proof argument by symmetry. 

Proof:: Take a cone in general, and build a circle that rotates on a 
axis. Rotate the circle just a tiny bit for it is bound to get stuck 
or impeded by the upward slanted walls of the cone. Rotate as far as 
you possibly can. Now filling in the area upwards is far smaller than 
filling in the area downwards. Hence, only 1 axis of symmetry, not 2 
axes of symmetry. Define Oval as having 1 axis of symmetry. Thus a 
oval, never an ellipse. QED 

The above two proofs are Synthetic Geometry proofs, which means they 
need no numbers, just some concepts and axioms to make the proof work. 
A Synthetic geometry proof is where you need no numbers, no coordinate 
points, no arithmetic, but just using concepts and axioms. A Analytic 
Geometry proof is where numbers are involved, if only just coordinate 
points. 

Array:: Analytic Geometry proof that Cylinder section= Ellipse//Conic 
section = Oval, never ellipse 

Now I did 3 Experiments and 3 models of the problem, but it turns out 
that one model is superior over all the other models. One model is the 
best of all. 

That model is where you construct a cone and a cylinder and then 
implant a circle inside the cone and cylinder attached to a handle so 
that you can rotate the circle inside. Mine uses a long nail that I 
poked holes into the side of a cylinder and another one inside a cone 
made from heavy wax paper of magazine covers. And I used a Mason or 
Kerr used lid and I attached them to the nail by drilling two holes 
into each lid and running a wire as fastener. All of this done so I 
can rotate or pivot the circle inside the cylinder and cone. You need 
a long nail, for if you make the models too small or too skinny, you 
lose clarity. 

ARRAY, Analytic Geometry Proof, Cylinder Section is a Ellipse:: 


              E 
             __ 
      .-'              `-. 
    .'                    `. 
  /                         \ 
 ;                           ; 
| G          c              | H 
 ;                           ; 
  \                         / 
   `.                     .' 
      `-.    _____  .-' 
                F 

The above is a view of a ellipse with center c and is produced by the 
Sectioning of a Cylinder as long as the cut is not perpendicular to 
the base, and as long as the cut involves two points not larger than 
the height of the cylinder walls. What we want to prove is that the 
cut is always a ellipse, which is a plane figure of two axes of 
symmetry with a Major Axis and Minor Axis and center at c. 

Side view of Cylinder EGFH above with entry point cut at E and exit 
point cut at F and where c denotes the central axis of the cylinder 
and where x denotes a circle at c parallel with the base-circle of 
cylinder 

|                              | 
|                              | E 
|                              | 
|                              | 
|x            c              |x 
|                              | 
|                              | 
|                              | 
|F                            | 
|                              | 
|                              | 
|                              | 


So, what is the proof that figure EGFH is always an ellipse in the 
cylinder section? The line segment GH is the diameter of the circle 
base of cylinder and the cylinder axis cuts this diameter in half such 
that Gc = cH. Now we only need to show that Fc = cE. This is done from 
the right triangles cxF and cxE, for we note that by Angle-Side-Angle 
these two right triangles are congruent and hence Fc = cE, our second 
axis of symmetry and thus figure EGFH is always an ellipse. QED 



Array proof:: Analytic Geometry proof that Conic section= Oval// never ellipse 

ARRAY, Analytic Geometry Proof, Conic Section is a Oval, never an ellipse:: 


         A 
      ,'"   "`. 
   /            \ 
C |     c       | D 
 \               / 
    ` . ___ .' 
         B 

The above is a view of a figure formed from the cut of a conic with 
center c as the axis of the cone and is produced by the Sectioning of 
a Cone as long as the cut is not perpendicular to the base, and as 
long as the cut is not a hyperbola, parabola or circle (nor line). 
What we want to prove is that this cut is always a oval, never an 
ellipse. An oval is defined as a plane figure of just one axis of 
symmetry and possessing a center, c, with a Major Diameter as the axis 
of symmetry and a Minor Diameter. In our diagram above, the major 
diameter is AB and minor diameter is CD. 

Alright, almost the same as with Cylinder section where we proved the 
center was half way between Major Axis and Minor Axis of cylinder, 
only in the case of the Conic, we find that the center is half way 
between CD the Minor Diameter, but the center is not halfway in 
between the Major Diameter, and all of that because of the reason the 
slanted walls of the cone cause the distance cA to be far smaller than 
the distance cB. In the diagram below we have the circle of x centered 
at c and parallel to base. The angle at cx is not 90 degrees as in 
cylinder. The angle of cAx is not the same as the angle cBx, as in the 
case of the cylinder, because the walls of the cone-for line segments- 
are slanted versus parallel in the cylinder. Triangles cAx and cBx are 
not congruent, and thus, the distance of cA is not equal to cB, 
leaving only one axis of symmetry AB, not CD. 

     /  \A 
 x/  c  \x 
B/         \ 

Hence, every cut in the Cone, not a hyperbola, not a parabola, not a 
circle (not a line) is a Oval, never an ellipse. 

QED 

--Archimedes Plutonium

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#423444 — Re: Archimedes "Total Failure" Plutonium flunked the Math Test of a lifetime-generation test

Math Failure Archimedes Plutonium <plutonium.archimedes@gmail.com> fails:

>AP writes: pretty stupid of John Conway to never admit the ellipse is never
>a conic, always a cylinder section, when even his students in class can 
>prove it to John Conway by a cone, cylinder can and circle lid-- the 

<snip>

Poor Archie, still struggling with the conic section problem...

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