Question 87
Let $I$ be the incentre of acute-angled triangle $A B C$. Let the incircle meet $B C$, $C A$, and $A B$ at $D$, $E$, and $F$, respectively. Let line $E F$ intersect the circumcircle of the triangle at $P$ and $Q$, such that $F$ lies between $E$ and $P$. Prove that $\angle D P A + \angle A Q D = \angle Q I P$.
(Slovakia)
(Slovakia)