A nice problem

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Phlembac Adib Hasan
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A nice problem

Unread post by Phlembac Adib Hasan » Tue Jan 03, 2012 10:01 am

(From Geometry Revisited) $ABC$ is a triangle and let $G$ is its centroid.A line through $G$ meets $AB$ and $AC$ at point $P$ and $Q$, respectively.Prove that (with respect to sign) \[ \frac {BP} {PA} + \frac { CQ } {QA} =1 \]
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Nadim Ul Abrar
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Re: A nice problem

Unread post by Nadim Ul Abrar » Tue Jan 03, 2012 4:26 pm

Note that $PA=BP+2PE \Rightarrow \frac{BP}{PA}+\frac{2PE}{PA}=1 $

Now via menelaus we have $\frac{QA.CG.PE}{CQ.EG.PA}=1 \Rightarrow \frac{CQ}{QA}=\frac{2PE}{AP}$.
$\frac{1}{0}$

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Phlembac Adib Hasan
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Re: A nice problem

Unread post by Phlembac Adib Hasan » Tue Jan 03, 2012 6:39 pm

My proof was also the same. This problem taught me Manelaus. :D
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