下列偏微分方程中，属于二阶、线性、齐次的是（ ）
A:
B:
C:
D:
A:
B:
C:
D:
举一反三
- 下列偏微分方程中，属于二阶、线性、非齐次的有（ ） A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/2d9756d86089460ea64d904bde2a5130.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/97ceeefb489e4b9282a626fed7620618.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/4fd730158c314452b756b78c6e61e7b1.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/237e8593c50641698325880106ebe179.png">
- 某反应在标准态和等温等压条件下，在任何温度都能自发进行的条件是（ ）。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/63c6a7b5b3114c1095cb68d96ebd27ec.png" />< 0，<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/d11dd437fcbe440d886e25a9a04f2c0e.png" />> 0 B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/63c6a7b5b3114c1095cb68d96ebd27ec.png" />> 0，<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/d11dd437fcbe440d886e25a9a04f2c0e.png" />> 0 C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/63c6a7b5b3114c1095cb68d96ebd27ec.png" />> 0，<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/d11dd437fcbe440d886e25a9a04f2c0e.png" />< 0 D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/63c6a7b5b3114c1095cb68d96ebd27ec.png" />< 0，<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/d11dd437fcbe440d886e25a9a04f2c0e.png" />< 0
- 如图所示电路的逻辑表达式F=（ ）。<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/8655693a417e4e43a32e0732ed533c96.png" /> A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/beda73211aea49f082d9137fd4eb0526.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/7388c99ee0824f20bcf85893934a2f6a.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/9a5c81e78b344c79a9389e932a7f55ce.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/82193a9a030243728012b02e15718987.png" />
- 下列积分中等于零的是 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/beafcd1bd9a045e4bef379cba1d6c572.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/fc2d4b861cbf43eb8a27dde67b97f680.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/d9c33bed53f147c4b62a3f7553d496e0.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/4e50aaa9bf42400db5b7573935fc97e4.png" />
- 下列各表达式正确的是（）。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/c00e74606aff46b3bd686c1cbb405da6.gif" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/a9452605ec5b4dfc8fede5ae6baae903.gif" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/316677d9b4fe41d09b0ef5f8b18e4a0b.gif" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/1d4a5808f5524820897bf23dd439ad0c.gif" />