名校
1 . 有下列说法:
①在残差图中,残差点比较均匀地落在水平带状区域内,说明选用的模型比较合适;
②
用来刻画回归效果,
的值越小,说明模型拟合效果越好;
③比较两个模型的拟合效果,可以比较残差平方和的大小,残差平方和越小的模型,拟合效果越好.
其中正确命题的序号为_________ .
①在残差图中,残差点比较均匀地落在水平带状区域内,说明选用的模型比较合适;
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
③比较两个模型的拟合效果,可以比较残差平方和的大小,残差平方和越小的模型,拟合效果越好.
其中正确命题的序号为
您最近一年使用:0次
2 . 已知A、B为抛物线
上两点,直线
过焦点F,A、B在准线上的射影分别为C、D,则①
轴上恒存在一点K,使得
;②
;③存在实数
使得
(点O为坐标原点);④若线段
的中点P在准线上的射影为T,有
.中正确说法的序号________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9de36529148d5e73cc4ff68b8f5e3fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d487fe76b23b2accc0b08c5386a987db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c822c3e065399046a64954bda65f7c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e49fd1a2597f67240c9b98f77df71b74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a670efc425a7cef956399d242b883f31.png)
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名校
3 . 下列说法正确的是_________ (请把你认为正确说法的序号都填上).
(1)函数
的最小正周期为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86ebba6ed1add0fe647c0226614b9290.png)
(2)若命题
:“
,使得
”,则
:“
,均有
”
(3)
中,
是
的充要条件;
(4)已知点N在
所在平面内,且
,则点N是
的重心;
(1)函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f8639eae0325866c58acd33302151d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86ebba6ed1add0fe647c0226614b9290.png)
(2)若命题
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1485a4756c56f1126b9825d5019d544c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/264dab145ceba44696a6ee63b1e1549d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ffc1bb9d53a27d484396ad74d6a26e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c780149aef1bd77162e85f7f8906a6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba1c77d129b56255baf3d76eb2a6c2ff.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19dc38d888741a1b2e95fe0773a48c38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca51be437b1a97ca92aa1159ab71102c.png)
(4)已知点N在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/202f58538466612afcf186e5c65d9a05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
您最近一年使用:0次