One of those hand-waving proofs

by math_explorer, Sep 18, 2010, 1:53 PM

Quote:
46337
$A, B, C$ are points on a line in that order. A line through $B$ intersects the circle with diameter $AC$ at $P$ and $Q$, the circle with diameter $AB$ at $R$, and the circle with diameter $BC$ at $S$. Prove that $PR$ = $QS$. (Note that it doesn't matter if $P$ and $Q$ are swapped.)

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The next problem was pseudopseudopseudorandomly selected from Geometry Unsolved Problems, because I skipped the first two numbers, which were both larger than 5000. Ha.
213436
I don't want to type the whole thing, so a link will have to do. My goodness, more terminology.
geo problem
geometry
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