下列各项中，为某五阶行列式带有正号的项是（ ）.
A:
B:
C:
D:
A:
B:
C:
D:
举一反三
- 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" />
- 已知某网络函数单位冲激响应如图所示，则网络函数表达式可能为（ ） 。<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/1ea32deea3ff4a79adbdf2fd1d50f685.png" /> A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/3daa0643dbc0480582ecdded649049b2.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/38da044f0efb404a840b6cad69f53996.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/97e060f9767b46cbaa03ec6a04f8baed.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/fc42e852a3ca49ff9fcb9d5efe69a1a9.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" />
- 下列命名正确的是( ) A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/45d758d675564df2b279142c14ae9e2e.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/4889492bf6634f04b7c4e5c944f66ed8.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/70bc128530144f07aa006af0ebe6a989.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/ddcdceddcb9a49bf8ab24aea015a7a9a.png">