2012·四川自贡·三模
1 . 对于三次函数
,定义
是
的导函数
的导函数,若方程
有实数解
,则称点
为函数
的“拐点”,可以证明,任何三次函数都有“拐点”,任何三次函数都有对称中心,且“拐点”就是对称中心,请你根据这一结论判断下列命题:
①任意三次函数都关于点
对称:
②存在三次函数
有实数解
,点
为函数
的对称中心;
③存在三次函数有两个及两个以上的对称中心;
④若函数
,则: ![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/cbdd6b14556e4870b23f8c1dcfe4e3ad.png?resizew=373)
其中正确命题的序号为_____ (把所有正确命题的序号都填上).
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/21ac331a5b0e4b30b00b0bfc8770a14a.png?resizew=213)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/60cd76baa3484586a3fab13c0e7d75f7.png?resizew=41)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/ca5c67acb37e4344aca4776bfadbb516.png?resizew=61)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/9b22cb4ef676428f863b199d569eff7a.png?resizew=65)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/4aeca168313f4352a09e9371cf7fe4f8.png?resizew=67)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/bed6f27974b441c4901f45d1999f3071.png?resizew=19)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/4a1972c93ff74273a10d6e3a25e47433.png?resizew=75)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/ca5c67acb37e4344aca4776bfadbb516.png?resizew=61)
①任意三次函数都关于点
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/86f6c82c145b4959a4570a0ff352e9e1.png?resizew=104)
②存在三次函数
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/9263178288534479a8555ceebddfcf6e.png?resizew=64)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/bed6f27974b441c4901f45d1999f3071.png?resizew=19)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/4a1972c93ff74273a10d6e3a25e47433.png?resizew=75)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/ca5c67acb37e4344aca4776bfadbb516.png?resizew=61)
③存在三次函数有两个及两个以上的对称中心;
④若函数
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/6f90ab20b1234a0b8c61bb78c5026c69.png?resizew=155)
![](https://img.xkw.com/dksih/QBM/2013/6/7/1571240628027392/1571240633196544/STEM/cbdd6b14556e4870b23f8c1dcfe4e3ad.png?resizew=373)
其中正确命题的序号为
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9-10高二下·江西新余·阶段练习
2 . 对于曲线C:
给出下面四个命题:
①曲线C不可能表示椭圆;
②当
时,曲线C表示椭圆;
③若曲线C表示双曲线,则
或![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/251cbabe54e140d281b0d9c84dc06e9b.png?resizew=39)
④若曲线C表示焦点在
轴上的椭圆,则![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/32e3e517d7c64bf7860c5178ca7cdb45.png?resizew=63)
其中所有正确命题的序号为______________
![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/d12fe525f35c45a79b51360540a5d4c7.png?resizew=108)
①曲线C不可能表示椭圆;
②当
![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/f2013ce21044405ea43183b322041cb0.png?resizew=60)
③若曲线C表示双曲线,则
![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/8dd5f2c41ae94164b458b4b878524670.png?resizew=35)
![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/251cbabe54e140d281b0d9c84dc06e9b.png?resizew=39)
④若曲线C表示焦点在
![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/a821bd9c2ceb452c9860fbecc46a081e.png?resizew=13)
![](https://img.xkw.com/dksih/QBM/2010/7/8/1569784929886208/1569784934670336/STEM/32e3e517d7c64bf7860c5178ca7cdb45.png?resizew=63)
其中所有正确命题的序号为
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名校
3 . 研究变量x,y得到一组样本数据,进行回归分析,有以下结论:
①残差平方和越小的模型,拟合的效果越好;
②用相关指数
来刻画回归效果,
越小说明拟合效果越好;
③若变量y和x之间的相关系数为
,则变量y和x之间的负相关很强;
④残差点比较均匀地落在水平的带状区域中,说明选用的模型比较合适.
以上正确说法的序号是______________ .
①残差平方和越小的模型,拟合的效果越好;
②用相关指数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
③若变量y和x之间的相关系数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0903883bbad97cb553e6a803deb5e331.png)
④残差点比较均匀地落在水平的带状区域中,说明选用的模型比较合适.
以上正确说法的序号是
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2023-03-10更新
|
498次组卷
|
4卷引用:浙江省杭州市之江高级中学2022-2023学年高二下学期期中数学试题
浙江省杭州市之江高级中学2022-2023学年高二下学期期中数学试题安徽省芜湖市第一中学2018-2019学年高二下学期期中理科数学试题(已下线)4.2 一元线性回归模型(同步练习)-【素养提升—课时练】2022-2023学年高二数学湘教版选择性必修第二册检测 (基础篇)(已下线)8.2 一元线性回归模型及其应用(题型专训)-2022-2023学年高二数学同步精品课堂(人教A版2019选择性必修第三册)
14-15高一上·湖南·期末
4 . 在平面直角坐标系内,设
、
为不同的两点,直线
的方程为
, 设
有下列四个说法:
①存在实数
,使点
在直线
上;
②若
,则过
、
两点的直线与直线
平行;
③若
,则直线
经过线段
的中点;
④若
,则点
、
在直线
的同侧,且直线
与线段
的延长线相交
上述说法中,所有正确说法的序号是_____________
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/f04ec3c0af7e4d2f9e230d8dfdce1a53.png?resizew=67)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/efadc7f0be644e829aca6f2026d81594.png?resizew=67)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/844046db10fc4179ba8f3bb4b5f4e832.png?resizew=9)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/c5e37406297c4cc0b7a3a3977001c165.png?resizew=99)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/12d4558f9ca74d0391b0c3e19d8ba5d1.png?resizew=117)
①存在实数
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/b2a6ae7937424fb785f53e040aac9f3b.png?resizew=15)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/ceacd8043356434a835a6434856ddce3.png?resizew=19)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/844046db10fc4179ba8f3bb4b5f4e832.png?resizew=9)
②若
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/3eecf3a886884412b0e438e21231171b.png?resizew=36)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/8aab72ce677146d191625325eef9351b.png?resizew=21)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/ceacd8043356434a835a6434856ddce3.png?resizew=19)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/844046db10fc4179ba8f3bb4b5f4e832.png?resizew=9)
③若
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/0ee1eee61ac14a10914e8d2d17de77b4.png?resizew=47)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/844046db10fc4179ba8f3bb4b5f4e832.png?resizew=9)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/87e7a3ca0b2441a6aab5f3d60f715a74.png?resizew=31)
④若
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/5791add589924e8cacfaf9ceeb324072.png?resizew=36)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/8aab72ce677146d191625325eef9351b.png?resizew=21)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/ceacd8043356434a835a6434856ddce3.png?resizew=19)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/844046db10fc4179ba8f3bb4b5f4e832.png?resizew=9)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/203e1bf9fdaf441a827a51c2bff2fce9.png?resizew=9)
![](https://img.xkw.com/dksih/QBM/2014/3/3/1571538912477184/1571538918326272/STEM/87e7a3ca0b2441a6aab5f3d60f715a74.png?resizew=31)
上述说法中,所有正确说法的序号是
您最近一年使用:0次