3.已知正四棱柱ABCD-A1B1C1D1.AB=1.AA1=2.點(diǎn)E為CC1中點(diǎn).點(diǎn)P為BD1中點(diǎn). 證明EF為BD1與CC1的公垂線, 證:建立如圖的坐標(biāo)系.得B.D1.F(..1).C1.E. 即EF⊥CC1.EF⊥BD1 . 故EF是為BD1 與CC1的公垂線. 查看更多

 

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精英家教網(wǎng)已知正四棱柱ABCD-A1B1C1D1.AB=1,AA1=2,點(diǎn)E為CC1中點(diǎn),點(diǎn)F為BD1中點(diǎn).
(1)證明EF為BD1與CC1的公垂線;
(2)求點(diǎn)D1到面BDE的距離.

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已知正四棱柱ABCD-A1B1C1D1.AB=1,AA1=2,點(diǎn)E為CC1中點(diǎn),點(diǎn)F為BD1中點(diǎn).
(1)證明EF為BD1與CC1的公垂線;
(2)求點(diǎn)D1到面BDE的距離.

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已知正四棱柱ABCD-A1B1C1D1.AB=1,AA1=2,點(diǎn)E為CC1中點(diǎn),點(diǎn)F為BD1中點(diǎn).
(1)證明EF為BD1與CC1的公垂線;
(2)求點(diǎn)D1到面BDE的距離.

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已知正四棱柱ABCD-A1B1C1D1.AB=1,AA1=2,點(diǎn)E為CC1中點(diǎn),點(diǎn)F為BD1中點(diǎn).
(1)證明EF為BD1與CC1的公垂線;
(2)求點(diǎn)D1到面BDE的距離.

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已知正四棱柱ABCD-A1B1C1D1.AB=1,AA1=2,點(diǎn)E為CC1中點(diǎn),點(diǎn)F為BD1中點(diǎn).
(1)證明EF為BD1與CC1的公垂線;
(2)求點(diǎn)D1到面BDE的距離.

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