MathDB

5

Part of 2013 IMAC Arhimede

Problems(1)

romanian angle chasing, circumcircle, incircle and angle bisectors related

Source: IMAC Arhimede 2013 p5

9/26/2018
Let Γ\Gamma be the circumcircle of a triangle ABCABC and let EE and FF be the intersections of the bisectors of ∠ABC\angle ABC and ∠ACB\angle ACB with Γ\Gamma. If EFEF is tangent to the incircle γ\gamma of △ABC\triangle ABC, then find the value of ∠BAC\angle BAC.
geometrycircumcircleincircleAngle Chasinganglesangle bisector