Author Topic: math problem. help?  (Read 5015 times)

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Offline turiqwalrus

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math problem. help?
« on: April 08, 2011, 01:08:03 pm »
this problem was not solved by the entire math department!
can any of you? if you can, please show work.
thanks
I got 18.088

EDIT: find the bottom chord
« Last Edit: April 08, 2011, 03:02:08 pm by turiqwalrus »

Offline Builderboy

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Re: math problem. help?
« Reply #1 on: April 08, 2011, 01:40:59 pm »
What are we trying to find?

Offline turiqwalrus

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Re: math problem. help?
« Reply #2 on: April 08, 2011, 03:01:21 pm »
the chord that runs along the bottom.
« Last Edit: April 08, 2011, 03:01:48 pm by turiqwalrus »

Offline feerik

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Re: math problem. help?
« Reply #3 on: April 08, 2011, 03:26:15 pm »
the form reminds me of the donkey hatO_o

Offline jnesselr

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Re: math problem. help?
« Reply #4 on: April 08, 2011, 03:34:37 pm »
Is that a right-angle symbol in the top right triangle?  And is that entire line 8 or what?

Offline turiqwalrus

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Re: math problem. help?
« Reply #5 on: April 08, 2011, 03:41:36 pm »
Is that a right-angle symbol in the top right triangle?

yes.
And is that entire line 8 or what?
no. the 8 is the segment

Offline AngelFish

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Re: math problem. help?
« Reply #6 on: April 08, 2011, 03:44:10 pm »
May we assume that the intersection of all of the triangles is the center of the circle?
∂²Ψ    -(2m(V(x)-E)Ψ
---  = -------------
∂x²        ℏ²Ψ

Offline turiqwalrus

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Re: math problem. help?
« Reply #7 on: April 08, 2011, 03:45:08 pm »
yes.

Offline AngelFish

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Re: math problem. help?
« Reply #8 on: April 08, 2011, 03:58:48 pm »
To be honest, it's unsolvable without making further assumptions or having more information. Here's the solution given all of the information available. Note that B is the angle of the upper undefined arc and A is the angle of the lower undefined arc that includes the secant we're trying to solve for.

Given K≈10.4432583147

20.56920350997≈(2(K2)-4K*Cos(A))+(2(K2)-4K*Cos(B))
« Last Edit: April 08, 2011, 03:59:21 pm by Qwerty.55 »
∂²Ψ    -(2m(V(x)-E)Ψ
---  = -------------
∂x²        ℏ²Ψ

Offline phenomist

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Re: math problem. help?
« Reply #9 on: April 08, 2011, 07:05:56 pm »
Three possible interpretations:

Radius is 8/sin(50) about 10.4432583147 = R

1) There is no upper part. Answer is 2sin(80)R = 20.5692
2) The perpendicular is an extension to the other side of the triangle. Answer is 2sin(65)R = 18.9296
3) The sides are extensions to each other. Answer is 2sin(40)R = 13.4256

Basically, the answer is 2R*sin(A/2) where A is the vertex angle of the bottom triangle.

It's underconstrained.

EDIT: By reverse-engineering your answer (@OP), it appears that you assume that the angle at the bottom is 120 degrees.
« Last Edit: April 08, 2011, 07:12:56 pm by phenomist »
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Offline turiqwalrus

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Re: math problem. help?
« Reply #10 on: April 08, 2011, 07:16:29 pm »
yeah... I just noticed that :P
it's unsolvable without more information

Offline 42vs.1337

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Re: math problem. help?
« Reply #11 on: May 01, 2011, 03:17:36 am »
next time please think a bit on how to solve the problem before wastin my time.
i spent like 7+ years on it and ended up completley FAILING!
if you think about it for just 7 nano sconds you\'ll notice that it is wrong.
dunt be like gabriel carol and make wrong asummptions about polygons.

Offline shmibs

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Re: math problem. help?
« Reply #12 on: May 01, 2011, 03:33:54 am »
hullo there, you, and welcome. you should introduce yourself via the board created for that purpose =D
you should also read the rules, particularly the first,
Quote from: the rules
Innapropriate content and actions include, but are not limited to, the following:

1: Flaming, bigotry, trolling or any other provocative comment aimed toward an user or group of users.
, and next time please think a bit on how to properly voice your opinion without resorting to hyperbola aimed at rebutting a fellow member. he may have posted without having thought it through properly beforehand, but he also went on to admit this fact and does not need to be reminded of his mistake again, particularly in an insulting manner.
we hope you enjoy your stay here ;)
« Last Edit: May 01, 2011, 03:55:34 am by shmibs »

Offline Munchor

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Re: math problem. help?
« Reply #13 on: May 01, 2011, 05:44:48 am »
next time please think a bit on how to solve the problem before wastin my time.
i spent like 7+ years on it and ended up completley FAILING!
if you think about it for just 7 nano sconds you\'ll notice that it is wrong.
dunt be like gabriel carol and make wrong asummptions about polygons.

You should definitely read the rules, like shmibs said, and that was a very rude comment. Please apologize to Freyaday.

Offline turiqwalrus

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Re: math problem. help?
« Reply #14 on: May 01, 2011, 03:42:58 pm »
next time please think a bit on how to solve the problem before wastin my time.
i spent like 7+ years on it and ended up completley FAILING!
if you think about it for just 7 nano sconds you\'ll notice that it is wrong.
dunt be like gabriel carol and make wrong asummptions about polygons.

You should definitely read the rules, like shmibs said, and that was a very rude comment. Please apologize to Freyaday.
to Freyaday? he was ranting about me...

next time please think a bit on how to solve the problem before wastin my time.
i spent like 7+ years on it and ended up completley FAILING!
if you think about it for just 7 nano sconds you\'ll notice that it is wrong.

if it took 7+ years, how can you figure out that it's wrong in 7 nanoseconds?
Quote
dunt be like gabriel carol and make wrong asummptions about polygons.
who is gabriel carol anyways ???
« Last Edit: May 01, 2011, 03:45:05 pm by turiqwalrus »