三棱锥A﹣BCD中，平面ABD与平面BCD的法向量分别为 n1→ ， n2→ ，若＜ n1→ ， n2→ ＞= π3 ，则二面角A_刷题宝

题干

三棱锥A﹣BCD中，平面ABD与平面BCD的法向量分别为 n1→ ， n2→ ，若＜ n1→ ， n2→ ＞= π

3

，则二面角A﹣BD﹣C的大小为（）

A： $\frac{π}{3}$

B： $\frac{2 π}{3}$

C： $\frac{π}{3}$ 或 $\frac{2 π}{3}$

D： $\frac{π}{6}$ 或 $\frac{π}{3}$

上一题下一题 0.0难度选择题更新时间:2020-01-15 12:37:54

答案(点此获取答案解析）

C

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