边长为a的正四面体的高是多少了 正四面体边长为a，它的高是多少，外接球半径和内切球
\u6b63\u56db\u9762\u4f53\u8fb9\u957f\u4e3aa,\u9ad8\u4e3a\u591a\u5c11\u6b63\u56db\u9762\u4f53\u7684\u9ad8\u662f\u9876\u70b9\u5230\u5e95\u9762\u4e09\u89d2\u5f62\u7684\u4e00\u6761\u4e2d\u7ebf\u4e0a\u79bb\u6b64\u4e09\u89d2\u5f62\u9876\u70b9\u76842/3\u5904\u7684\u8fde\u7ebf\u3002\u6240\u4ee5\u7b54\u6848\u8bd5\u4e09\u5206\u4e4b\u6839\u53f7\u516da\u3002
1,\u6b63\u56db\u9762\u4f53\u7684\u9ad8h=a
2,\u5185\u5207\u7403\u76f4\u5f84=a\uff0c\u534a\u5f84r1=a/2
3,\u5916\u63a5\u7403\u534a\u5f84\u7684\u5e73\u65b9(r2)²=(a/2)²+(a/2)²=(2a²)/4
\u5916\u63a5\u7403\u534a\u5f84r2=\u221a[(2a²)/4]=[(\u221a2)/2]a
边长为a的正四面体的高是a
3分之根号6a 证明略、画不了图 把结论背住就行了
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