三角形abc中∠A=52°BE平分∠ABC,CE平分∠ACD,BE,CE,交于点E∠BEC=

问题描述:

三角形abc中∠A=52°BE平分∠ABC,CE平分∠ACD,BE,CE,交于点E∠BEC=

∵CE平分∠ACD
∴∠ACD = 2∠ECD
∵∠ACD = ∠B+∠A
∴∠ECD = ∠B/2 + ∠A/2
∵BE平分∠ABC
∴∠ECD = ∠B/2
∵∠ECD = ∠EBC + ∠E
∴∠ECD = ∠B/2 + ∠E
∴∠E = ∠A/2 = 26°