• 2022-11-04
    已知单位向量[img=10x19]1803dc6faf641de.png[/img],[img=8x24]1803dc6fb874b5c.png[/img]的夹角为45°,[img=49x26]1803dc6fc111356.png[/img]与[img=10x19]1803dc6fc9b3d41.png[/img]垂直,则k=__________.
    未知类型:{'options': ['', '3', '', ''], 'type': 102}