Let [tex]K[/tex] be a circle with centre [tex]O[/tex]. A second circle [tex]L[/tex] passes through [tex]O[/tex] and cuts [tex]K[/tex] at two other points [tex]A[/tex] and [tex]B[/tex]. Let [tex]P[/tex] be a point on arc [tex]AOB[/tex] and extend line segment [tex]BP[/tex] to intersect [tex]K[/tex] at a second point [tex]Q[/tex]. Prove that the bisector of angle [tex]APQ[/tex] passes through [tex]O[/tex].