Let ABCABC be an acute triangle with AB<ACAB < AC. Let JJ be the center of the AA-excircle of ABCABC. Let DD be the projection of JJ on line BCBC. The internal bisectors of angles BDJBDJ and JDCJDC intersect lines BJBJ and JCJC at XX and YY, respectively. Segments XYXY and JDJD intersect at PP. Let QQ be the projection of AA on line BCBC. Prove that the internal angle bisector of QAP\measuredangle QAP is perpendicular to line XYXY.

Remark. The AA-excircle of the triangle ABCABC is the circle outside the triangle which is tangent to the lines ABAB, ACAC, and the line segment BCBC.