在△ABC中,∠A=α,∠ABC的平分线与∠ACD的平分线交与点A1,得∠A1;∠A1BC的平分线与∠A1CD的平分线相交于A2,得∠A2;…;∠A2008BC的平分线与∠A2008CD的平分线相交于点A2009,得∠A2009,则∠A2009=( )
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![在△ABC中,∠A=α,∠ABC的平分线与∠ACD的平分线交与点A1,得∠A1;∠A1BC的平分线与∠A1CD的平分线相交于A2,得∠A2;…;∠A2008BC的平分线与∠A2008CD的平分线相交于点A2009,得∠A2009,则∠A2009=( )](/uploads/image/z/1648898-26-8.jpg?t=%E5%9C%A8%E2%96%B3ABC%E4%B8%AD%2C%E2%88%A0A%3D%CE%B1%2C%E2%88%A0ABC%E7%9A%84%E5%B9%B3%E5%88%86%E7%BA%BF%E4%B8%8E%E2%88%A0ACD%E7%9A%84%E5%B9%B3%E5%88%86%E7%BA%BF%E4%BA%A4%E4%B8%8E%E7%82%B9A1%2C%E5%BE%97%E2%88%A0A1%EF%BC%9B%E2%88%A0A1BC%E7%9A%84%E5%B9%B3%E5%88%86%E7%BA%BF%E4%B8%8E%E2%88%A0A1CD%E7%9A%84%E5%B9%B3%E5%88%86%E7%BA%BF%E7%9B%B8%E4%BA%A4%E4%BA%8EA2%2C%E5%BE%97%E2%88%A0A2%EF%BC%9B%E2%80%A6%EF%BC%9B%E2%88%A0A2008BC%E7%9A%84%E5%B9%B3%E5%88%86%E7%BA%BF%E4%B8%8E%E2%88%A0A2008CD%E7%9A%84%E5%B9%B3%E5%88%86%E7%BA%BF%E7%9B%B8%E4%BA%A4%E4%BA%8E%E7%82%B9A2009%2C%E5%BE%97%E2%88%A0A2009%2C%E5%88%99%E2%88%A0A2009%3D%EF%BC%88+%EF%BC%89)
在△ABC中,∠A=α,∠ABC的平分线与∠ACD的平分线交与点A1,得∠A1;∠A1BC的平分线与∠A1CD的平分线相交于A2,得∠A2;…;∠A2008BC的平分线与∠A2008CD的平分线相交于点A2009,得∠A2009,则∠A2009=( )
在△ABC中,∠A=α,∠ABC的平分线与∠ACD的平分线交与点A1,得∠A1;∠A1BC的平分线与∠A1CD的平分线相交于
A2,得∠A2;…;∠A2008BC的平分线与∠A2008CD的平分线相交于点A2009,得∠A2009,则∠A2009=( )
在△ABC中,∠A=α,∠ABC的平分线与∠ACD的平分线交与点A1,得∠A1;∠A1BC的平分线与∠A1CD的平分线相交于A2,得∠A2;…;∠A2008BC的平分线与∠A2008CD的平分线相交于点A2009,得∠A2009,则∠A2009=( )
∵∠ABC与∠ACD的平分线交于点A1,
∴∠A1=180°- ∠ACD-∠ACB- ∠ABC
=180°- 1/2(∠ABC+∠A)-(180°-∠A-∠ABC)- 1/2∠ABC
= 1/2∠A=α/2¹ ;
同理可得∠A2= 1/2∠A1= α/2²
∴∠A2009=α/2*2009
∵∠ABC与∠ACD的平分线交于点A1,
∴∠A1=180°- ∠ACD-∠ACB- ∠ABC
=180°- 1/2(∠ABC+∠A)-(180°-∠A-∠ABC)- 1/2∠ABC
= 1/2∠A=α/2¹ ;
同理可得∠A2= 1/2∠A1= α/2²
∴∠A2009=α/2*2009
在△ABC中,∠A=α,∠ABC的平分线与∠ACD的平分线交与点A1,得∠A1;∠A1BC的平分线与∠A1CD的平分线相交于
A2,得∠A2;…;∠A2008BC的平分线与∠A2008CD的平分线相交于点A2009,得∠A2009,则∠A2009=( ? )