若L是上半椭圆 取顺时针方向，则 的值为( ).https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/87464b2710b74edd919a1014709f8862.png
举一反三
- 设L是圆域 按顺时针方向的边界曲线，则https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/f2e053ac144d460d96a9627cd769114d.png
- 若是上半椭圆取顺时针方向,则 的值为( ).https://image.zhihuishu.com/zhs/doctrans/docx2html/202004/21eef708e831438182b154855b2f9d24.png
- 设A=<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/bc546fc03fdb4ba3b7e6b144b6371d7f.png" />，B=Р(Р(A)) 下列（ ）表达式不成立。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/6e615703da60435893f9e9a9273e12e5.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/64c831067d054e71a6c76f43849d450d.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/72023a5250e44c12b98923044194f13d.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/c48e039a739c4502830eee7ae0ac1678.png" />
- 下列函数为有界函数的是（ ）. A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/8b29e23e896d48fbb32316cf188c7897.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/00a2ecf9d8814be9996a25fafd9205f8.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/90cc2cce15bb40a08b7c102e9d5eb020.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/df59aabc218b4c67afbd897414705118.png">
- 关于螺纹画法,正确的是 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/9ccba4619f94435c98b9ae7570b942d9.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/4bc6e6bda3eb4599aac46a7006ed3c17.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/cbdbd84b5748432d8d69e846b62109af.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/177c1236fbdd49ee899e6f362f3211e6.png" />