1 . 如图1,在正方体
中,已知
为
的中点. 则二面角
的余弦值为.
![](https://img.xkw.com/dksih/QBM/2018/12/4/2089525975711744/2091151512068096/STEM/96c9dc7b-ffbf-4c35-afde-4fa293d85852.png?resizew=232)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13ed825cd4933c6e8c41fe93cf1200b2.png)
![](https://img.xkw.com/dksih/QBM/2018/12/4/2089525975711744/2091151512068096/STEM/96c9dc7b-ffbf-4c35-afde-4fa293d85852.png?resizew=232)
A.![]() | B.![]() | C.![]() | D.![]() |
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2 . 若集合
,则集合
中的元素个数为.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31c5b14e4a0f934abc3af8b4d00e90ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
A.4030 | B.4032 |
C.![]() | D.![]() |
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3 . 已知集合
为全集
的子集,且
,则下面结论正确的是( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/668e4734f35b8853b66c9e9c160ef1b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bb6829284515c480f59dc6f6bb971dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/399706b09fce8935f58cca7e3c565490.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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4 . 设
为
的三个内角.命题
,命题
,则
是
的( )条件.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b23beb7fa35ed321584f95c7507b8b78.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7741ef450c57879c0e2c94ca30e66d83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48ad3f260c5bbb691f57cd9153c76621.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63011498e73731346645de7100f55ab3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/859701760e76f1b0de2480da41acacaf.png)
A.充分非必要 | B.必要非充分 | C.充分必要 | D.既非充分又非必要. |
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5 . 已知
与
关于直线l对称,则l的方程为.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/091e86ca89e484b331fd90125a5e5af3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af74f34216645828a1c1408a263604bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/091e86ca89e484b331fd90125a5e5af3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c79eec23259b8ba41f55ad86e3d5aa5.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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6 . 已知等比数列
,则
=.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/630d5ca791f47806bd629bf73fb2d8bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5607c019c731e7deb19a5fc1cf3b7373.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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7 . 设
表示不超过实数x的最大整数.则方程
的所有实数根的个数为.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4f5908d6a1217e493ed7586b6964dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1382051edc9f8c4d2bfc600707ac2a88.png)
A.0 | B.1 | C.2 | D.3 |
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8 . 若
,且
,则
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6e2092db9d6194a4e372454346f706c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7185406a6edf89d870352820a967d85f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892560dcff6af9f66a3f735652f69dd7.png)
A.-1 | B.1 | C.2 | D.3 |
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9 . 若某几何体的三视图如图所示,则该几何体的体积为.
![](https://img.xkw.com/dksih/QBM/2018/12/13/2095812317167616/2096830333255680/STEM/d2e691fc2b8f4d6c81dff484cbbf95be.png?resizew=387)
![](https://img.xkw.com/dksih/QBM/2018/12/13/2095812317167616/2096830333255680/STEM/d2e691fc2b8f4d6c81dff484cbbf95be.png?resizew=387)
A.1 | B.2 | C.![]() | D.![]() |
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10 . 已知复数
,且
,
,则
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5df4170b8341d74deb829de56703955e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9cebcfa43df5b197723cb22fc39cda76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41372b05d336a2f64bb7ff915987640d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54787ce15648b3d5f0fb4007c1569189.png)
A.![]() | B.![]() | C.3 | D.![]() |
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