A simple "Geometry Revisited" problem...

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Labib
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A simple "Geometry Revisited" problem...

Unread post by Labib » Mon Apr 25, 2011 10:53 pm

After Munir Sir's life threatening speeches(!) @ the special camp, had to visit the BDMO forum.... :lol:
I've started to solve "Geometry Revisited" exercises,so I'm gonna try to post problems from there...both problems that I liked and problems I can't solve.

This is from the very first exercise of the book....
I really liked it and it seemed a pretty good problem to start with...

$PROBLEM :$

Let $p$ and $q$ be the radii of two circles through $A$, touching $BC$ at $B$ and $C$, respectively.
Then prove that, $pq=R^2$.

Here, $R$ is the circumcircle of the $\triangle ABC$.
Last edited by Labib on Tue Apr 26, 2011 10:04 pm, edited 1 time in total.
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*Mahi*
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Re: A simple "Geometry Revisited" problem...

Unread post by *Mahi* » Tue Apr 26, 2011 6:21 pm

Hey , please state the problem clearly. Here you missed to mention what $R$ is.
Last edited by *Mahi* on Wed Apr 27, 2011 12:32 pm, edited 1 time in total.
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Re: A simple "Geometry Revisited" problem...

Unread post by Labib » Tue Apr 26, 2011 9:58 pm

Sorry about that. It was a mistake.

I will edit it right away!! :)
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Re: A simple "Geometry Revisited" problem...

Unread post by Labib » Tue Apr 26, 2011 10:13 pm

BTW, Mahi, I've solved it. I used the law of sines.(It was a problem relating the law of sines).
So you might consider posting your full proof. You can always hide it as you did with the hint.
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Re: A simple "Geometry Revisited" problem...

Unread post by *Mahi* » Wed Apr 27, 2011 12:40 pm

Labib wrote:BTW, Mahi, I've solved it. I used the law of sines.(It was a problem relating the law of sines).
So you might consider posting your full proof. You can always hide it as you did with the hint.
The hint was for other people... I don't think you took that personally... though I've deleted it.
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Re: A simple "Geometry Revisited" problem...

Unread post by Labib » Wed Apr 27, 2011 10:30 pm

Hey, why would I take it personally bro....
I do like using hints... :D
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Re: A simple "Geometry Revisited" problem...

Unread post by *Mahi* » Thu Apr 28, 2011 5:48 pm

You wrote it wrong again :?
$R$ would be the circumradius.
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Re: A simple "Geometry Revisited" problem...

Unread post by Labib » Fri Apr 29, 2011 10:57 pm

Sorry, I don't have the editing option now.... :-s
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Re: A simple "Geometry Revisited" problem...

Unread post by photon » Thu May 05, 2011 11:10 pm

i have got a proof,but i want to confirm...is $BC$ a tangent?mine is for tangent $BC$.
@labib bhai,if i write my real name ,then ''photon'' may lose its mystery...isn't $''photon''$ good,huh? :)
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Re: A simple "Geometry Revisited" problem...

Unread post by Labib » Thu May 05, 2011 11:49 pm

Photon ain't bad, But I ain't Sherlock Homes. I can't stand mysteries. :D
So you better tell me your name in PM.
(I guess you might one of those two whizzes from Khulna, though I might not be correct.)
And YES, $BC$ is a tangent of the circles with those two radii.
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