设闭曲线L所围区域的面积为S,则S=( )
A: [img=107x48]18036fe44af1247.png[/img]
B: [img=107x48]18036fe453daed2.png[/img]
C: [img=107x48]18036fe45ca5ff4.png[/img]
D: [img=107x48]18036fe46553a43.png[/img]
A: [img=107x48]18036fe44af1247.png[/img]
B: [img=107x48]18036fe453daed2.png[/img]
C: [img=107x48]18036fe45ca5ff4.png[/img]
D: [img=107x48]18036fe46553a43.png[/img]
举一反三
- 在半径为r的圆中开一个平行四边形孔(如图所示),则图形对z轴的惯性矩是 。[img=332x322]18035c27cf05cef.jpg[/img] A: [img=107x48]18035c27d6c8f72.png[/img] B: [img=107x48]18035c27df1574e.png[/img] C: [img=107x48]18035c27e8223a9.png[/img] D: [img=107x48]18035c27f12a9aa.png[/img]
- 图示截面对x,y轴的惯性积为:[img=578x479]18034a1efafcb97.png[/img] A: [img=127x30]18034a1f0345cf7.png[/img] B: [img=142x42]18034a1f0b82b08.png[/img] C: [img=133x32]18034a1f1444d52.png[/img] D: [img=107x48]18034a1f1cf40f8.png[/img]
- 设矩阵[img=79x74]1803e3096125d8c.png[/img],[img=107x48]1803e30969fe3f5.png[/img],则[img=31x26]1803e30972b05a7.png[/img]= A: 0 B: 1 C: 2 D: 3
- 设曲线L为圆周[img=78x26]18036fe47007bcb.png[/img],则[img=107x48]18036fe477f98cb.png[/img]的值为 未知类型:{'options': ['', '', '1', ''], 'type': 102}
- 图示截面对x,y轴的惯性积是:[img=578x479]1802f41b3c15bb7.png[/img] A: [img=127x30]1802f41b44a5c0d.png[/img] B: [img=142x42]1802f41b4cdc4dc.png[/img] C: [img=133x32]1802f41b566b8b8.png[/img] D: [img=107x48]1802f41b5ecd45e.png[/img]