题目内容
.如图,A是以EF为直径的半圆上的一点,作AG⊥EF交EF于G,又
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155016791.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155324330.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155016791.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155324330.jpg)
.证明,连结AF,AK
∵EF是直径
∴∠EAF=90°
又∵AG⊥EF
∴∠AFE=∠GAE
又∵∠AKE=∠AFE
∴∠AKE=∠EAG
∠AEK=∠AEB
∴△AEB∽△KEA
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155632249.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156412234.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156884503.jpg)
∵EF是直径
∴∠EAF=90°
又∵AG⊥EF
∴∠AFE=∠GAE
又∵∠AKE=∠AFE
∴∠AKE=∠EAG
∠AEK=∠AEB
∴△AEB∽△KEA
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155632249.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156412234.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156884503.jpg)
.证明,连结AF,AK
∵EF是直径
∴∠EAF=90°
又∵AG⊥EF
∴∠AFE=∠GAE
又∵∠AKE=∠AFE
∴∠AKE=∠EAG
∠AEK=∠AEB
∴△AEB∽△KEA
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155632249.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156412234.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156884503.jpg)
∵EF是直径
∴∠EAF=90°
又∵AG⊥EF
∴∠AFE=∠GAE
又∵∠AKE=∠AFE
∴∠AKE=∠EAG
∠AEK=∠AEB
∴△AEB∽△KEA
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026155632249.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156412234.jpg)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408230026156884503.jpg)
![](http://thumb.zyjl.cn/images/loading.gif)
练习册系列答案
相关题目