Cho hình chóp $S.ABC$ có $SA\perp \left(ABC\right)$ , tam giác $ABC$ đều, $AB=a$ , góc giữa $SB$ và mặt phẳng $\left(ABC\right)$ bằng $60°$ . Gọi $M$ , $N$ lần lượt là trung điểm của $SA$ , $SB$ . Tính thể tích của khối chóp $S.MNC$ .

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Một số câu hỏi khác có thể bạn quan tâm.

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• Find a mistake in the four underlined parts of the sentence and correct it:

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