Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
| From | moroney@world.std.spaamtrap.com (Michael Moroney) |
|---|---|
| Newsgroups | sci.math, sci.physics |
| Subject | Re: Archimedes Plutonium flunked the Math Test of a lifetime-generation test |
| Date | 2018-05-25 18:48 +0000 |
| Organization | The World : www.TheWorld.com : Since 1989 |
| Message-ID | <pe9lph$u07$1@pcls7.std.com> (permalink) |
| References | <414bd92f-292b-4cf3-bb10-49f4c929791c@googlegroups.com> <caffea40-8681-4ef8-ac16-2006c2043cd2@googlegroups.com> <05a608ff-63a6-42ea-b98c-c5b7dc7d1cbc@googlegroups.com> <4de25a26-4078-40f0-8c7a-7ca4f3e90efb@googlegroups.com> |
Cross-posted to 2 groups.
Cone? Did you say cone? Here's a real cool proof about the cone!
Below you will find a simple *proof* that shows that certain conic
sections are ellipses.
Some preliminaries:
Top view of the conic section and depiction of the coordinate system used
in the proof:
^ x
|
-+- <= x=h
.' | `.
. | .
| | |
' | '
`. | .'
y <----------+ <= x=0
Cone (side view):
.
/|\
/ | \
/b | \
/---+---' <= x = h
/ |' \
/ ' | \
/ ' | \
x = 0 => '-------+-------\
/ a | \
Proof:
r(x) = a - ((a-b)/h)x and d(x) = a - ((a+b)/h)x, hence
y(x)^2 = r(x)^2 - d(x)^2 = ab - ab(2x/h - 1)^2 = ab(1 - 4(x - h/2)^2/h^2.
Hence (1/ab)y(x)^2 + (4/h^2)(x - h/2)^2 = 1 ...equation of an ellipse
qed
Back to sci.math | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
page1&2 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-24 09:48 -0700
Re: page1&2 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium - Yet another repeat of crap. alouatta.coibensis@gmail.com - 2018-05-24 10:01 -0700
2Alouatta talks Berkeley-- Denis Auroux, Richard Bamler, Robert Bryant, never a Picture of Fundamental Theorem of Calculus//are you as dumb as Alouatta //your students deserve better Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-25 11:16 -0700
Re: Archimedes Plutonium flunked the Math Test of a lifetime-generation test moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-05-25 18:48 +0000
Moroney calls MIT Harvard coneheads// Bernard Burke, George Clark , Jeffrey Goldstone//never realizing the Real Electron = muon, proton=840MeV, .5MeV = Dirac's monopole Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-25 12:14 -0700
page3&4 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-25 11:18 -0700
page5&6 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-25 20:17 -0700
page7&8 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-27 07:36 -0700
page9&10 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-27 13:07 -0700
page11&12 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium Archimedes Plutonium <plutonium.archimedes@gmail.com> - 2018-05-27 13:28 -0700
Re: Archimedes Plutonium flunked the Math Test of a lifetime-generation test moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-05-27 20:55 +0000
Re: _Burse calls 25 years crazy-- Manfred Einsiedler, Paul Embrechts, Giovanni Felder of ETH, no picture diagram of Calculus proof// still believing proton is 938MeV electron .5MeV when they are 840MeV, 105MeV moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-05-27 20:24 +0000
Re: page1&2 TEACHING TRUE MATHEMATICS, 2018, by Archimedes Plutonium bursejan@gmail.com - 2018-05-27 12:58 -0700
csiph-web