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| Started by | moroney@world.std.spaamtrap.com (Michael Moroney) |
|---|---|
| First post | 2019-03-01 22:35 +0000 |
| Last post | 2019-03-01 22:35 +0000 |
| Articles | 1 — 1 participant |
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Re: Archimedes "just not bolted down too tight in the first place" Plutonium flunked the physics lifetime-generation test moroney@world.std.spaamtrap.com (Michael Moroney) - 2019-03-01 22:35 +0000
| From | moroney@world.std.spaamtrap.com (Michael Moroney) |
|---|---|
| Date | 2019-03-01 22:35 +0000 |
| Subject | Re: Archimedes "just not bolted down too tight in the first place" Plutonium flunked the physics lifetime-generation test |
| Message-ID | <q5cc2r$olq$3@pcls7.std.com> |
AlzheimerPlutonium <plutonium.archimedes@gmail.com> fails at math and science:
>Apparently everyone at Reed College is as blind and ignorant of the ellipse
> as is Moroney. Here is a proof the ellipse is never a conic and was shown
You want to learn from Reed College why the ellipse is a conic section?
Perhaps they will teachthis!
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
x-no-archive: yes
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