是常微分方程。（ ）http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/564a3d9bd0ed4a268e246fb606dca8a5.png
举一反三
- 在圆柱壳轴对称弯曲问题的基本方程中，有三个方程式自动满足的，我们只需要求解三个平衡方程，它们是： A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/3c3eb06997f449be89a76e35f8073f1f.png"> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/7c87e3a7dc5445688a702fe5364a8635.png"> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/c6739033a3da46ce92e809ea34907621.png"> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/55a259aaa0b842c99f0d9c3b9176cae3.png">
- 内压球形容器的应力为： A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/7a7e20156c8c4502840fc258ffe21c74.png"> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/6b137ba6e7464b2c8122eced2a3d45cd.png"> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/3c032f5116a04b288400df17925e39c2.png"> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/85ca21668f4045e2b864897bc3795fdf.png">
- http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/75f92f05d558450f9e68e52200633e6b.png
- http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/f6ebadff38ba4857862e848abba5ff8f.png
- 设为某函数的全微分，则（ ）。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/2d16c7c4c93d419c908abafce90d46a2.png