如图,C在直线BE上,∠ABC与∠ACE的角平分线交于点A1, (1)若∠A=60°,求∠A1的度数; (2)若∠A=m,求∠A1的度数; (3)在(2)的条件下,若再作∠A1BE、∠A;1CE的平分线,交于点A2;再
问题描述:
如图,C在直线BE上,∠ABC与∠ACE的角平分线交于点A1,
(1)若∠A=60°,求∠A1的度数;
(2)若∠A=m,求∠A1的度数;
(3)在(2)的条件下,若再作∠A1BE、∠A;1CE的平分线,交于点A2;再作∠A2BE、∠A2CE的平分线,交于点A3;…;依此类推,则∠A2,∠A3,…,∠An分别为多少度?
答
∵∠A1=∠A1CE-∠A1BC
=
∠ACE-1 2
∠ABC1 2
=
(∠ACE-∠ABC)1 2
=
∠A.1 2
∴(1)当∠A=60°时,∠A1=30°;
(2)当∠A=m时,∠A1=
m;1 2
(3)依此类推∠A2=
m,∠A3=1 4
m,∠An=(1 8
)nm.1 2