1 . 在平面内,点
三点共线的充要条件是:对于平面内任一点
,有且只有一对实数
,满足向量关系式
,且
.类比以上结论,可得到在空间中,
四点共面的充要条件是:对于平面内任一点
,有且只有一对实数
满足向量关系式__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01225eca2322a6136314dedadcafa994.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d093706141016f4e2fde905738cd481e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5558c083d34cbb0a58d3ce1dc6f5778e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90a0889f0f80987c260cce05be4c84b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a14c388e1e2e5a2ff1ccf6caffbee0d.png)
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2018-03-01更新
|
447次组卷
|
2卷引用:【全国市级联考】山东省菏泽市2017-2018学年高二下学期期中考试数学(理)试题
2 . 已知
,
是正整数,
,当
时,则有
成立,当且仅当“
”取等号,利用上述结论求
,
的最小值______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2958030ec9d7543dda1f529593a915e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac7609ba927b00e031d2cf5651efec6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b9e3a68f7e0c78d37f3ac4d118e515e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfbd4e25575245b5688f4b6e395fcd1c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69b4ad01b8653e3e1383e27051a35c9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af1df2a8b51ea0efaaec4d6f96742e34.png)
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2019-11-08更新
|
211次组卷
|
4卷引用:山东省青岛市青岛第十七中学2020-2021学年高三上学期期中数学试题
山东省青岛市青岛第十七中学2020-2021学年高三上学期期中数学试题(已下线)2010-2011学年湖北省荆州中学高一下学期期中考试理科数学卷上海市奉城高级中学2018-2019学年高一上学期期中数学试题上海市第二中学2018-2019学年度高二下学期期末数学试题
3 . 将正整数排成如图所示,其中第
行,第
列的那个数记为
,则数表中的
应记为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7600d2cfbdc6146db96cc545706004f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60a84bece3ec757cb4c8e4c75d410a78.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2030a7c508abe4b2a03bc702cf7692d.png)
![](https://img.xkw.com/dksih/QBM/2017/12/8/1834125226205184/1836084629020672/STEM/21c8fbb2ef5749258d7bdcb7536026ec.png?resizew=249)
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4 . 设
,计算知
,由此猜想,得到的正确结论是下列的__________ .(写出你认为正确的结论序号)
①
②
③
④
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/729e05eb4677b287296b3abb75d67486.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dbb2bd637b70f149a08d4ef30e6c9bf.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94166d484f4ff95208cb299a0ff9db23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ecce57529d8f6ee9c83900a43f96f65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe689324e6c21c71b27fed8240041342.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98b4487bc392b39fc1dd322ee94468c0.png)
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名校
5 . 如图甲所示,在直角
中,
,
是垂足,则有
,该结论称为射影定理.如图乙所示,在三棱锥
中,
平面
,
平面
,
为垂足,且
在
内,类比直角三角形中的射影定理,则有__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9178fc8b5d65aa75fa9196294a0db7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68b5ccc091f33c45e82a26b6cb14450c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bef9e71f2ea82268222533ca9c6d5d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ba6fb5afc7fd86226985c0bd5e53b70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5c3aec3e9c309e72d096c0a86f4e1a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/787ac5e13622afab5e9f8603afe42356.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/397bf976a5d6ea47153fb564cc8ea190.png)
![](https://img.xkw.com/dksih/QBM/2017/12/23/1844727254212608/1845195758706688/STEM/25ffd42be57c4db1bea6216895e972e3.png?resizew=79)
![](https://img.xkw.com/dksih/QBM/2017/12/23/1844727254212608/1845195758706688/STEM/f84d09b8501240059b717406c34b541c.png?resizew=68)
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2017-12-24更新
|
356次组卷
|
5卷引用:【全国百强校】山东省济宁市第一中学2017-2018学年高二下学期期中考试数学(文)试题
【全国百强校】山东省济宁市第一中学2017-2018学年高二下学期期中考试数学(文)试题2016届江苏省清江中学高三考前一周双练三模数学试卷皖江名校2018届高三12月份大联考数学(理)试题(已下线)2018年高考二轮复习测试专项【苏教版】专题九 算法 推理与证明 复数2019届福建省厦门市双十中学高三上学期第一次月考理科数学试题
6 . 已知结论“a1、a2∈R+,且a1+a2=1,则
+
≥4:若a1、a2、a3∈R+,且a1+a2+a3=1,则
+
+
≥9”,请猜想若a1、a2、…、an∈R+,且a1+a2+…+an=1,则
+
+…+
≥________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/252de0a549286d1b1721ae96d5832654.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a03fee94205c63211128cbadfa17b810.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/252de0a549286d1b1721ae96d5832654.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a03fee94205c63211128cbadfa17b810.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/478e5abb0d8b335bedffa548968eb1e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/252de0a549286d1b1721ae96d5832654.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a03fee94205c63211128cbadfa17b810.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b7e761be88728b3db50c2abd4377c12.png)
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7 . 传说古希腊毕达哥拉斯学派的数学家经常在沙滩上画点或用小石子表示数.他们研究过如图所示的三角形数:
...
将三角形数
记为数列
,将可被5整除的三角形数按从小到大的顺序组成一个新数列
,可以推测:
是数列
中的第________ 项.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/29/0a8fdd34-1e1d-4db2-bb12-8bad9b1dbaaa.png?resizew=215)
将三角形数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4cf15b68264d9c2336fb49477ddcfb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5dc8249abbfbed2e588391c0c917a75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
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8 . 从下列等式中归纳出一个一般性的结论.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edbc244bab9a219d7f9b26ab4ea738a3.png)
;
;
________________________________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edbc244bab9a219d7f9b26ab4ea738a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5ce9b3c15e5df4dc1ca696dafd67461.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37e44441b2eea2fe81eb64f4974d6396.png)
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9 . 设
,复数
,当![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c57bbef89a37f1a3808c0ceeac0c22.png)
_________ 时,
为纯虚数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40e72f6b2ef3329828cb8fc873eeba7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/423c3bad10fad71ae09d075b94b03b2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c57bbef89a37f1a3808c0ceeac0c22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
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10 . 观察数表:
根据数表中所反映的规律,第
行与第
列的交叉点上的数应该是__________ .
1 | 2 | 3 | 4 | …第一行 |
2 | 3 | 4 | 5 | …第二行 |
3 | 4 | 5 | 6 | …第三行 |
4 | 5 | 6 | 7 | …第四行 |
第一列 | 第二列 | 第三列 | 第四列 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0876215b2fd463d151523cd3c6b447.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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