如图,过半径为R的球面上一点P作三条两两垂直的弦PA、PB、PC,
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/9ef1b5f4-a6b9-4e68-993a-67377292ceeb.png?resizew=197)
(1) 求证:PA2+PB2+PC2为定值;
(2)求三棱锥P—ABC的体积的最大值.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/9ef1b5f4-a6b9-4e68-993a-67377292ceeb.png?resizew=197)
(1) 求证:PA2+PB2+PC2为定值;
(2)求三棱锥P—ABC的体积的最大值.
2019高三·全国·专题练习 查看更多[1]
(已下线)5.2 直线 平面平行与垂直的判定与性质[文] -《备战2020年高考精选考点专项突破题集》
更新时间:2019-12-15 10:23:30
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