设是圆周，方向为逆时针方向，则。（ ）http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/3888f5f3fd4d48bb95a479c97a4ad93a.png
举一反三
- 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">
- 设区域，则的值为。( ）http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/468d5951e23a436ba9cd1954573d5aef.png
- 设f(x)连续函数，则=（ ）。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/d61df8d810544f27ada3ecb86c2d853a.png
- 设z=f(x,v) ，v=v(x,y) ，其中f,v具有一阶连续偏导数，则（ ）。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/64ca8940dd6e4835901f2da3b85b7607.png
- http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/75f92f05d558450f9e68e52200633e6b.png