Question 52
Let $ABC$ be an isosceles triangle with $AC = BC$ and let $k$ be a circle with center $C$ and radius less than the altitude $CH$, $H \in AB$. Lines through $A$ and $B$ are tangent to $k$ at points $P$ and $Q$ lying on the same side of the line $CH$. Prove that the points $P$, $Q$ and $H$ are collinear.