1 . 如图,由半径为2的四分之一圆面绕其半径所在直线
旋转一周,形成的几何体底面圆的圆心为
,
是几何体侧面上不在
上的动点,
是
的直径,
为
上不同于
,
的动点,
为
的重心,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/f11a6a21-8835-4666-89b2-720d1f873a49.png?resizew=277)
(1)证明:
平面
;
(2)当三棱锥
体积最大时,求直线
与面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e28a42f6d431be3660146e09ac57684.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/f11a6a21-8835-4666-89b2-720d1f873a49.png?resizew=277)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b8badfeb9e7556486e02ab60df4dd32.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)当三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4357d5744046d4d44abb09e1ee35fcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed6a7cf4e7edb951adc4170a0975a573.png)
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名校
2 . 古希腊数学家欧几里得在《几何原本》中描述了圆锥曲线的共性,并给出了圆锥曲线的统一定义,只可惜对这一定义欧几里得没有给出证明.经过了500年,到了3世纪,希腊数学家帕普斯在他的著作《数学汇篇》中,完善了欧几里得关于圆锥曲线的统一定义,并对这一定义进行了证明.他指出,到定点的距离与到定直线的距离的比是常数
的点的轨迹叫做圆锥曲线;当
时,轨迹为椭圆;当
时,轨迹为抛物线;当
时,轨迹为双曲线.现有方程
表示的曲线是双曲线,则
的取值范围为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/168b3e4b1d6f04226fa2687a72a268b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42b7ac29311c13aa538f3f48cb513b0d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09dbcaa127022fbd6b6f13345196408a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a58c44592477e5cab15cd165ff9b3d78.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e5a0893d8d44a7c6445489474cadc44.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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2021-05-28更新
|
1275次组卷
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8卷引用:广东省惠州市2021届高三下学期一模数学试题