如图所示: ∠AOB=114°
∠AOE=(1/2)∠AOB
由∠BOC=2∠AOC,得∠AOC=(1/3)∠AOB
∠EOC=∠AOE-∠AOC=(1/2)∠AOB-(1/3)∠AOB=(1/6)∠AOB=114°/6=19°
∠EOC=1/2∠AOB-1/3∠AOB=1/6×114°=19°
∠EOC=∠BOC-∠BOE∠BOC=∠AOB*2/3=76°∠BOE=∠AOB/2=57°所以∠EOC=∠BOC-∠BOE=76°-57°=19°