下列微分方程中常微分方程的是( )
A:
B:
C:
D:
A:
B:
C:
D:
举一反三
- 图示结构C截面弯矩为<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/4f75b4fba9ff4be1b04a5e100c86c65e.png" /> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/145877d7a442497f9fe1266fa394ba2e.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/1b6f8295e7bc44b0b8a2bee20e062fc4.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/18776e34a7504dfcbe40fbdf73958b14.png" /> D: 0
- 下列尺寸标注正确的是（ ） A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/79ed6f04ee2f415c917c9f280eccf07e.png"> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/4677ac7155c849bebe9d2ffd7458f4c4.png"> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/489ad68ff6294831bc43fa08990b59b7.png"> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/e829c514224942f1926c1823be08d3e7.png">
- 下列各表达式中错误的是__ A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/dd20f9d2c1984b1f95ffd89fdf3fed61.png"> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/a7138f62245042a4a604eee2ce27ae93.png"> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/53b05040965a40629cf24d6c90bc7e27.png"> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/8bbfc40de0d6420aa10e572ce4a7b5dd.png">
- 在下图中，螺纹连接画法正确的是（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/388e6231e1fb4ef09858a435d5076944.jpg" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/5c2ff529f94044ffaf8ccbc591499df6.jpg" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/578fcb9927c044a4b982bf3e7e7616a3.jpg" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/bb9122c2834242f4afba03761d066fb8.jpg" />
- 下列配合物属于螯合物的是（ ） A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/8f51868d3100497c9f78fe09ba550e3f.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/025b639d0fe9456997a0191bdeb0019a.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/154fd181ff4d421d96ab4d50e3052020.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/fbd3f97989994e40a247c9ea17663bd0.png" />