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MC4 Geometry Proofs Problem 6

 
 
YuDL的头像
MC4 Geometry Proofs Problem 6
YuDL - 2019年10月20日 Sunday 14:18
 

Problem 6 is not true. I drew my figure with Geogebra and it doesn't work.

 
InstructorAreteem的头像
Re: MC4 Geometry Proofs Problem 6
InstructorAreteem - 2019年10月21日 Monday 13:50
 

Sorry, the problem is messed up.  The correct version should be:

Let $P$ be the intersection of the diagonals of cyclic quadrilateral $ABCD$.  Let $K,L,M,N$ be the projection of $P$ at the four sides.  Show that quadrilateral $KLMN$ has an inscribed circle.  In addition, if $\overline{AC}\perp\overline{BD}$, let $R$ be the circumradius of $ABCD$ and $d$ be the distance between circumcenter $O$ and $P$, find the inradius of $KLMN$.


The packet has been updated.

YuDL的头像
Re: MC4 Geometry Proofs Problem 6
YuDL - 2019年10月21日 Monday 16:01
 

Alright, thanks!