<Tri-2024-2105>,hint
Suppose circumcircle of triangle MCQ cuts AC and AM at C and T ,respectively
Since <QCC'=<QC'C=90-C. Hence CC'=2 MC sin (90-C)=2R sinA cosC
AC'=AC-CC'=2RsinB -2R sinA cosC=(2R sin(A+C)-2RsinA cosC)=
2R (sinAcosC +cosA sinC-sinA cosC)=2R sinC cosA.
Hence AC xAC'=2R sinB x 2R sinC cosA=AT x AM, <MTQ=90
Suppose circumcircle of triangle MBP cuts AB and AM at B' and T'
Similarly AB x AB'=2R x 2R cosA sinB sinC=AC x AC'
Hence AT=AT'. <MT'P=90. Hence AM and PQ are perpendicular. A,T,Q are collinear.
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