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- A ratio describing the shape of a conic section. 描述圆锥曲线部分形状的比率。
- A fixed point whose relationship with a directrix determines a conic section. 焦点一个与准线的关系决定圆锥形状的定点
- The fixed curve traversed by a generatrix in generating a conic section or a cylinder. 准线穿过产生圆锥部分或圆柱的母线而形成的固定曲线
- A conic section whose plane is not parallel to the axis, base, or generatrix of the intersected cone. 圆锥的一部分，其切面既不平行于轴和基面，也不平行于圆锥母线
- A conic section whose plane is not parallel to the axis,base,or generatrix of the intersected cone. 圆锥的一部分，其切面既不平行于轴和基面，也不平行于圆锥母线
- The ratio of the distance of any point on a conic section from a focus to its distance from the corresponding directrix. This ratio is constant for any particular conic section. 离心率二次曲线上任何一点到焦点的距离与到准线的距离之比对任一特定二次曲线来说，这个比值都是一个常数
- Given a hexagon inscribed in a conic section, the three pairs of the continuations of opposite sides meet on a straight line, called the Pascal line. 已知一个六边形内接于一条圆锥曲线，那么这个六边形对边的交点位于同一条直线上。
- The ratio of the distance of any point on a conic section from a focus to its distance from the corresponding directrix.This ratio is constant for any particular conic section. 离心率二次曲线上任何一点到焦点的距离与到准线的距离之比对任一特定二次曲线来说，这个比值都是一个常数
- A conic section. 圆锥部分
- A Conic Section and a Straight Line 一条圆锥曲线和一条直线
- a fixed reference point on the concave side of a conic section. 圆锥截面凹面的固定参考点。
- The polar line of a point with respect to a conic. 一点相对于一条二次曲线的极线。
- a fixed reference point on the concave side of a conic section 圆锥截面凹面的固定参考点
- a fixed point whose relationship with a directrix determines a conic section 一个与准线的关系决定圆锥形状的定点
- Conic sections and quadric surfaces. 二次曲线与二次曲面。
- the fixed curve traversed by a generatrix in generating a conic section or a cylinder 准线，穿过产生圆锥部分或圆柱的母线而形成的固定曲线
- (geometry) a ratio describing the shape of a conic section; the ratio of the distance between the foci to the length of the major axis. 描述圆锥曲线部分形状的比率；长轴长度与焦距距离比。
- Motion of planets and comets in conic sections; Kepler's laws. 在锥截面上的行星与彗星的运动;开普勒定律。
- According to the fUndamental theorem of coniC In projective geometry any five points can decide one conic section. 在射影几何中，二次曲线定理告诉我们任意五点可以决定一条二次曲线。
- The platonic school's most significant discovery was the conic sections. Plato学派的最重要发现是圆锥曲线。
