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linh2008
2 năm trước
Cho hình chóp SABC có đáy ABC là tam giác vuông cân tại B, AB = a. SA vuông góc với mặt phẳng (ABC) và SA= 2a . M là trung điểm SA. a) Tính góc tạo bởi mặt phẳng (SBC) và (SAB). b) Tính góc tạo bởi mặt phẳng (MBC) và (ABC). c) Tính góc tạo bởi mặt phẳng (SAC) và (SAB).
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