A simple "Geometry Revisited" problem...
After Munir Sir's life threatening speeches(!) @ the special camp, had to visit the BDMO forum....
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 $\triangle ABC$.
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.
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Re: A simple "Geometry Revisited" problem...
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.
Please read Forum Guide and Rules before you post.
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah | Mahi
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah | Mahi
Re: A simple "Geometry Revisited" problem...
Sorry about that. It was a mistake.
I will edit it right away!!
I will edit it right away!!
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Re: A simple "Geometry Revisited" problem...
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.
So you might consider posting your full proof. You can always hide it as you did with the hint.
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Re: A simple "Geometry Revisited" problem...
The hint was for other people... I don't think you took that personally... though I've deleted it.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.
Please read Forum Guide and Rules before you post.
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah | Mahi
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah | Mahi
Re: A simple "Geometry Revisited" problem...
Hey, why would I take it personally bro....
I do like using hints...
I do like using hints...
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Re: A simple "Geometry Revisited" problem...
You wrote it wrong again
$R$ would be the circumradius.
$R$ would be the circumradius.
Please read Forum Guide and Rules before you post.
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah | Mahi
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah | Mahi
Re: A simple "Geometry Revisited" problem...
Sorry, I don't have the editing option now.... :-s
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Re: A simple "Geometry Revisited" problem...
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?
@labib bhai,if i write my real name ,then ''photon'' may lose its mystery...isn't $''photon''$ good,huh?
Try not to become a man of success but rather to become a man of value.-Albert Einstein
Re: A simple "Geometry Revisited" problem...
Photon ain't bad, But I ain't Sherlock Homes. I can't stand mysteries.
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.
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.
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes
Learn how to write equations, and don't forget to read Forum Guide and Rules.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes