设A、B为两个互不相容的随机事件，且，则下列选项必然正确的是（ ）。https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/b0dd0722e98b4de281974e99338593fb.png
举一反三
- 设A、B为两个随机事件，则（ ）。https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/2ed8ca6978d44500bf10da3ba4eb180c.png
- 已知某变量分布属于钟形分布，且<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/c3c68d24239b47e3908a9fa39d3026e5.png">，则()。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/c289a674c3a949efb63ebfd7f5e17f73.png"> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/14899ead117944fd93b2513951e16161.png"> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/94c95d1322d84ebf9c0a99328b06d62b.png"> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/0f01a113b6e14ec8ac04e74d869aea49.png">
- 设积分环节的传递函数为G(s)=<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/2428288e967b4a34ade338e5ea5c6ce0.png" >，则其频率特性幅值A(ω)=（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/33a8b22368e4429585bd402fd07fd717.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/492828f883b74680b8b22570ec3522cf.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/0f44b2548a3c424eaa326c2bf10bece6.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/b93eaefa6dd04794949e3987d24a0991.png" >
- 已知某系统模拟图如图所示，则该系统数学模型为（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/7b331e776a454b34b3ce7514c85f55ce.png" ><img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/9b732439cb324b709c699aa7caf1bd43.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/3a6a819b0f204f1c861fa806fcff9bfa.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/296a376761a64a66a35f073904daa96f.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/6d22be023ff94910a3dc634670220912.png" >
- 若某系统的传递函数为G（s）=<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/40cffec1140048fda668f02b2697bfb6.png" >，则相应的频率特性G（jω）为（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/b0edaaca759a4b96b2746d371ba37485.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/17d6f581231244c386888754b3bf178d.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/e5485f9797b64853b91ce68c4697ff2e.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/5330c18e71b94abdbeaeff937486d18a.png" >