设在x=1处可导，则a=2，b=-2（ ）https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/9b49deb775aa49c0a73af81736a57e27.png

则（ ）https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/326780da120f4e96aff411584fb2e706.png

下列哪个结果是小振动问题的广义动量？ A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/88a2b0c72d824141a289c01e09f1645f.png"/> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/0803ba58456c4a3290e9bdb99759147f.png"/> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/ab24cb59059348a3b0ba6cc4e5fca989.png"/> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/916cb85fc9d84dda90b43a5f671092a9.png"/>

下列哪个结果等于拉格朗日函数对时间的导数？ A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/71e251af38d1445ba51641b664c72b4e.png"/> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/dc04aa798b3d404cb6c1f5e3d08b3242.png"/> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/007e2f33b2c04914b2c60d6c01def954.png"/> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/81eedf26bc254250a56919c9fb55ff1e.png"/>

用作花钵的植物高度控制在（ ）比较理想? A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/23b52d3a814d4457b43fbcbfd03aa855.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/93c6f6bddd444e5c932ec666b0eb7b08.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/249c386b45104bcfa5480f33469fdc8c.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201911/244d73f3b91047b1b5d67bd58af45514.png">