• 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]180319c44e54dfb.png[/img]
    A: [img=408x457]180319c45d592df.png[/img]
    B: [img=414x453]180319c46ac6054.png[/img]
    C: [img=405x454]180319c477a9aa6.png[/img]
    D: [img=421x449]180319c48427a0f.png[/img]