- 問題詳情:如圖所示,四面體SABC中,,∠SBA=45°,∠SBC=60°,M為AB的中點.則BC與平面SAB的夾角為()A.30° B.60°C.90° D.75°【回答】B知識點:空間中的向量與立體幾何題型:選擇題...
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