【简答题】![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/logo-new-ad743.png)
定义:到凸四边形一组对边距离相等,到另一组对边距离也相等的点叫凸四边形的准内点.如图1,PH=PJ,PI=PG,则点P就是四边形ABCD的准内点.
(1)如图2,∠AFD与∠DEC的角平分线FP,EP相交于点P.求证:点P是四边形ABCD的准内点.(2)分别画出图3平行四边形和图4梯形的准内点.(作图工具不限,不写作法,但要有必要的说明)(3)判断下列命题的真假,在括号内填“真”或“假”.①任意凸四边形一定存在准内点.(______)②任意凸四边形一定只有一个准内点.(______)③若P是任意凸四边形ABCD的准内点,则PA+PB=PC+PD或PA+PC=PB+PD.(______)
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAYAAABzenr0AAAA5ElEQVRYR2NkGGDAOMD2M+B0wKpVq9huv/jbxPD/fxwDA4MkhQ59zsDIuEhVgrkuLCzsF7JZOB3QOml5B8P//+UUWoyqnZGxszovsoI4B0xc9gyfzxmZmb2rcsK3IRvWMWm599///7fgcfTz6vwoKWId8B+f75kZGX0q8iK3kugAhur8KJRQxx0FE5fhdQC5UTPqgNEQGA2B0RAYDYHREBgNgaETAuTW96TqG7yt4tbRFhGRIQBqHTP9+8dIoDUMTxqk5AK8zXKYiaDWMYhNpANIaJYPdMdkwLtmpOZnctUPeDkAAP6tmiH1ggTLAAAAAElFTkSuQmCC)
手机使用
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/share-ico-3febd.png)
分享
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/link-f6c98.png)
复制链接
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/weibo-3e538.png)
新浪微博
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/qq-1c308.png)
分享QQ
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/wechat-a78ae.png)
微信扫一扫
微信内点击右上角“…”即可分享
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/report-ico-11843.png)
反馈
![收藏 - 刷刷题](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/coll-ico-cfcc9.png)
收藏
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/jubao-9c477.png)
举报
参考答案:
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/logo-new-ad743.png)
参考解析:
![](https://cos-cdn.shuashuati.com/shuashuati-web/2024-0521-0905-00/logo-new-ad743.png)