相關(guān)習(xí)題
科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本小題滿分13分)直三棱柱
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的直觀圖及其正視圖、側(cè)視圖、俯視圖如圖所示.
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(1)求證:
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面
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; (2)求點
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到平面
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的距離;
(3)求二面角
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的大小.
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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本小題滿分14分)
如圖,在三棱柱
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中,每個側(cè)面均為正方形,
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為底邊
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的中點,
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為側(cè)棱
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的中點.
(Ⅰ)求證:
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∥平面
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;
(Ⅱ)求證:
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平面

;
(Ⅲ)求直線
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與平面
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所成角的正弦值.

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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本小題滿分13分 )
如題18圖,已知四棱錐
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的底面是邊長為2的正方形,
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面

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分別為
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的中點.
(Ⅰ)求直線

與面
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所成的角;
(Ⅱ)求二面角

的大小.

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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本小題滿分12分)
如圖,在直三棱柱
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中,

,


,
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,點D是
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的中點
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
⑴求證:
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;
⑵求證:

平面

。
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科目:高中數(shù)學(xué)
來源:不詳
題型:填空題
設(shè)正方體的棱長為2 ,一個球內(nèi)切于該正方體。則這個球的體積是 。
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科目:高中數(shù)學(xué)
來源:不詳
題型:單選題
半徑為2cm的半圓紙片卷成圓錐放在桌面上,一陣風(fēng)吹倒它,它的最高處距桌面( )
A. | B. | C.2cm | D.4cm |
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科目:高中數(shù)學(xué)
來源:不詳
題型:填空題
如圖正六邊形
ABCDEF中,
P是△
CDE內(nèi)(包括邊界)的動點,設(shè)
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(
α、
β∈R),則
α+
β的取值范圍是
.

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科目:高中數(shù)學(xué)
來源:不詳
題型:單選題
對于平面

,下列命題中真命題是 ( )
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