Art of Problem Solving
AoPS Online
Math texts, online classes, and more
for students in grades 5-12.
Visit AoPS Online ‚
Books for Grades 5-12 Online Courses
Beast Academy
Engaging math books and online learning
for students ages 6-13.
Visit Beast Academy ‚
Books for Ages 6-13 Beast Academy Online
AoPS Academy
Small live classes for advanced math
and language arts learners in grades 2-12.
Visit AoPS Academy ‚
Find a Physical Campus Visit the Virtual Campus

2018 JBMO Problems

Revision as of 03:11, 1 August 2019 by Jatsing (talk | contribs) (Created page with "Problems/Problem 4 Let <math>\triangle ABC</math> and <math>A'</math>,<math>B'</math>,<math>C'</math> the symmetrics of vertex over opposite sides.The intersection of the circ...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Problems/Problem 4 Let $\triangle ABC$ and $A'$,$B'$,$C'$ the symmetrics of vertex over opposite sides.The intersection of the circumcircles of $\triangle ABB'$ and $\triangle ACC'$ is $A_1$.$B_1$ and $C_1$ are defined similarly.Prove that lines $AA_1$,$BB_1$ and $CC_1$ are concurent.

Retrieved from "https://artofproblemsolving.com/wiki/index.php?title=2018_JBMO_Problems&oldid=108119"