and 
of positive integers such that
,
be all positive integers smaller than 
such that 
for all 
is the largest positive integer that divides both 
and 
.
.
Y by Adventure10
Triangle 
,O=circumcenter of (ABC),OA=R,the A-excircle intersect (AB),(BC),(CA) at points F,D,E.
If the A-excircle has radius R prove that
,O=circumcenter of (ABC),OA=R,the A-excircle intersect (AB),(BC),(CA) at points F,D,E.If the A-excircle has radius R prove that
This post has been edited 1 time. Last edited by den_thewhitelion, Jun 15, 2016, 6:34 AM
be midpoint of arc 
not containing 
of circumcircle of 
be excenter. Then 
,
is parallelogram. And 
,
