如图,已知
,一条光线从点
出发后射向
边,若光线与
边垂直,则光线沿原路返回到点
,此时
,当
时,光线射到
边上的点
后,经
反射到线段
上的点
,易知
.若
,光线又会沿
原路返回到点
,此时
;若光线从点
出发后,经若干次反射能沿原路返回到点
,则锐角
的最小角
( )
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更新时间:2023-12-22 09:14:21
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