古希腊的哲学家柏拉图证明只存在5种正多面体,即正四、六、八、十二、二十面体,其中正八面体是由8个正三角形构成.如图,若正八面体的体积为
,则它的内切球半径为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd905fb4dd19b5cae348ecb12845f9ea.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/28/8e01fdec-6008-491a-9b9f-efb1404a6fff.png?resizew=116)
更新时间:2023-07-25 18:02:01
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