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MathNet 2007-part-01 — 187 problems (EN–VI) Question 35

Math Olympiad Vault · MathNet 2007-part-01 — 187 problems (EN–VI)

Question 35

Let $ABC$ be a triangle and $I$ its incentre. The circle with centre $I$ passing through $B$ meets $AC$ at the points $E$ and $F$, with $E$ and $F$ between $A$ and $C$ and distinct from them. The circumcircle of triangle $IEF$ meets the segments $EB$ and $FB$ at $Q$ and $R$, respectively. The line $QR$ meets the sides $AB$ and $BC$ at $P$ and $S$, respectively.
If $a$, $b$ and $c$ are the lengths of the sides $BC$, $CA$ and $AB$, respectively, compute the lengths of $BP$ and $BS$.