In the triangle ABC, AE bisects the angle BAC, angle c > angle B, f is on the extension line of AE, FD is perpendicular to D, try to deduce the relationship between angle EFD, angle B and angle C

In the triangle ABC, AE bisects the angle BAC, angle c > angle B, f is on the extension line of AE, FD is perpendicular to D, try to deduce the relationship between angle EFD, angle B and angle C

Angle c-angle B = = 2-angle EFD
180 ° - angle c-angle B = = angle a = = 2-angle EAB
Angle EAB + angle B = = angle fed
Angle fed + angle EFD = = 90 degrees
therefore
(180 ° - angle c-angle b) / 2 + angle B + angle EFD = = 90 °
So angle c-angle B = = 2-angle EFD