以下属于颤音记号的是（）。
A:
B:
C:
D:
A:
B:
C:
D:
举一反三
- 理想低通滤波器的传输函数<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/980b5b2a8d7044b697bc516003ea3acb.png" >是()。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/9a82e2e4ff27470da538512097ee6438.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/c079877bd52d471db3cd6e163f62adbb.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/52aa9898f12641d797c40e4d118bd733.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/a7815d7407f34172aeef470a6adc5f47.png" >
- 单边拉普拉斯变换<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/423a53f9b3bf40989454133dbce2d262.png" >的原函数等于（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/301dd2111ac64b0e8217cba94ba1a1ab.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/9772eee6eab34c208eba55009d00041b.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/42bfb5f864e34b5ca02a2a1cc9d9c71b.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/659eef6ba24b490191772fe51bab3c9a.png" >
- <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/f9d435b7e7604d1894a0359bb77eb2cc.png" >可写成以下正确的的表达式是（） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/e68f9f4bb1b640068bd1c9e988b3feca.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/1b379e5c6cd74b5da61e39e4ca32ad22.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/44f6ba8e2d6448f4bec35063ad0f689f.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/e25be7e84d1e4f358bb44dacefafd393.png" >
- 假定<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/71458e4f29a24928a4ad4d36e72ec6b9.png" >，以下关于z变换的性质描述，正确的是：（） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/545e8d644963417494a94eec7ae1bf50.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/04445d84fa3443968231a11a580079e2.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/5599b26833e546dfa3ab9c1c656c6581.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/fcc7d5135a714189b801863712e6b7f5.png" >
- 理想不失真传输系统的传输函数H（jω）是()。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/c53311dbea924826a56276a9472741b1.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/4f089e5988004320950aab7179fb9c28.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/2245b8eb25204e8e966be03821487380.png" >（<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/14618be7a9474fa09351a25e922eb774.png" >为常数） D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/9cba3ab48faa4d8980c79f62bb1f3da4.png" ><img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202002/64f67bce595243aaa13ded6089b431b1.png" >