C-15-Q074mediumsingle_mcq△APQR\triangle APQR△APQR এ QDQDQD মধ্যমা হলে PQ2+QR2=?PQ^2+QR^2 = ?PQ2+QR2=?a2(PD2+QD2)2(PD^2+QD^2)2(PD2+QD2)b