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充要条件

> 下列命题正确的是 [ ] A.“直线 a∥直线 b”的充分条件是“直线 a平行于直线 b所在的平面” B.“直线 l 平面 ”的充要条件是“直线 l垂直于平面内的无数条直线” C. a、 b不相交”的必要不充分条件是“直线 a、 b为异面直线” D. ∥平面 ”的必要不充分条件是“平面内存在不共线三点到平面的距离相等”

问题：

发布时间：2024-09-07

下列命题正确的是
[ ]
A.“直线 a∥直线 b”的充分条件是“直线 a平行于直线 b所在的平面”
B.“直线 l 平面 ”的充要条件是“直线 l垂直于平面内的无数条直线”
C. a、 b不相交”的必要不充分条件是“直线 a、 b为异面直线”
D. ∥平面 ”的必要不充分条件是“平面内存在不共线三点到平面的距离相等”

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