MathDB

Find an angle

Source: Indian Postal Coaching 2005

September 23, 2005

trigonometrygeometrycircumcirclecyclic quadrilateraltrig identitiesLaw of Sinesgeometry solved

Problem Statement

On the sides

AB

and

BC

of triangle

ABC

, points

K

and

M

are chosen such that the quadrilaterals

AKMC

and

KBMN

are cyclic , where

N = AM \cap CK

. If these quads have the same circumradii, find

\angle ABC