试题与答案

如图,三棱柱ABC—A1B1C1的底面是边长为2的正三角形且侧棱垂直于底面,侧棱长是

题型:问答题

题目:

如图,三棱柱ABC—A1B1C1的底面是边长为2的正三角形且侧棱垂直于底面,侧棱长是,D是AC的中点.

(1)求证:B1C∥平面A1BD;

(2)求二面角A1—BD—A的大小;

(3)求直线AB1与平面A1BD所成的角的正弦值.

答案:

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参考答案:B

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