曲线的拐点为. （ ）https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/a9a518950e9b4b0d82e340179fd3392c.png
举一反三
- 历史曲线构件的图标是( )。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/dfb6b619f35547c590f6e6c6aab95b3f.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/e7e0aaa5f6e84ba89410cc93b06a451a.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/354425393230484ab64d64a718bd9bad.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/1f794e99ed004e3190fa5181c32fe4e8.png" />
- x(t)的频谱为<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/5bcfe4175fcb4fabbdb5f40d00b5343e.png"/>，则<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/45b1670ebd6245ff99cc376a8048a645.png" />的频谱为（ ） A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/09bc7326832a4a1fba983e74c6d85d35.png"/> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/95fca346a74e4a6cbba601cd6d9e26bf.png"/> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/6bf6b83111ad45efac7eb9a37a245c68.png"/> D: 其余选项都不对
- 下面的表达式中，正确有？ A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/0e169fdf5e354dd4af80ea6386ddeca5.png"/> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/5124889b558b4186ba4140ca7692d717.png"/> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/f3d2d0d80b744f74899371cae0395a71.png"/> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/2af6ef9203e94ea2b993e1ad4d99e5d2.png"/>
- MCGS嵌入版组态软件，插入元件的图标为（ ）。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/994aaad4457d4681a93b1b7510a1cc32.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/8060157e508b4324b30674602b93d3ba.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/3d7b0289666143de92115d57616ffc86.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/c0ead39dc09740c1b3b682da3e3fa0d7.png">
- MCGS嵌入版组态软件，保存元件的图标为 （ ）。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/74ef980afc09440e9ee2705d1551a8ad.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/54b48895c9694d499f75d06b316d0ecc.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/3d3ad6a3d2854f04b8059a86c771beaa.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/e4580e0c56a44b569f108fb751a98f09.png">