• 2022-05-31
    求圆锥被两个平面切割后的水平投影和侧面投影。[img=291x433]180319c8dbcdd60.png[/img]
    A: [img=408x457]180319c8e98550d.png[/img]
    B: [img=414x453]180319c8f6c1f6f.png[/img]
    C: [img=405x454]180319c90349d41.png[/img]
    D: [img=421x449]180319c91013398.png[/img]