把一个等腰三角形以一条直边为轴旋转一周,得到一个立体图形.这个立体图形的体积是多少立方分米?长宽高都是3分米

来源：学生作业帮助网编辑：作业帮时间：2024/04/29 09:38:43

把一个等腰三角形以一条直边为轴旋转一周,得到一个立体图形.这个立体图形的体积是多少立方分米?长宽高都是3分米
把一个等腰三角形以一条直边为轴旋转一周,得到一个立体图形.这个立体图形的体积是多少立方分米?
长宽高都是3分米

把一个等腰三角形以一条直边为轴旋转一周,得到一个立体图形.这个立体图形的体积是多少立方分米?长宽高都是3分米
旋转后是以腰长为底面半径,腰长为高的圆锥体,体积是：
S=π3²×3/3=9π≈28.274333882308139146163790449516（立方分米）
（π=3.1415926535897932384626433832795）

3x3x3=27平方分米

两种情况：
1、以底边为轴，则得到以高为底面积半径的上下两相等的椎体。
2、以腰为轴，则得到棱长分别等于腰长和底边长的两个椎体。
但是，题目已知条件不对。三角形，何来长宽高？

把3.14*（3/2）^=6.751，之后再除以3就可以啦。

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