Advanced Geometric Problem & Solution (Twice a week update) Now 4776 problems posted.
<Qua-2026-815>, hint
AC and BD intersect at Q.
AQ+DQ>AD , BQ+CQ>BC---> AC+BD>BC+AD, similarly AC+BD>AB+CD
Hence AC+BD>1/2(AB+BC+CD+DA)
AB+BC>AC, AD+CD>AC AB+BC+CD+DA>2AC. Similarly AB+BC+CD+DA>2BD
Hence AC+BD<AB+BC+CD+DA
No comments:
Post a Comment