1 . 《五曹算经》是我国南北朝时期数学家甄鸾为各级政府的行政人员编撰的一部实用算术书.其第四卷第九题如下:“今有平地聚粟,下周三丈,高四尺,问粟几何?”其意思为“场院内有圆锥形稻谷堆,底面周长3丈,高4尺,那么这堆稻谷有多少斛?”已知1丈等于10尺,1斛稻谷的体积约为1.62立方尺,圆周率约为3,估算出堆放的稻谷约有( )
A.60.08斛 | B.171.24斛 |
C.61.73斛 | D.185.19斛 |
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2 . 对于在区间
上有意义的函数
,若满足对任意的
,
,有
恒成立,则称
在
上是“友好”的,否则就称
在
上是“不友好”的.现有函数
.
(1)当
时,判断函数
在
上是否“友好”;
(2)若函数
在区间
上是“友好”的,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57b85a97933a1d984f6e484b4021c800.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09760796d5ac6dfe5593fff41264b46c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1a8c69aaecfbe4d8bd7cf01a3b79c50.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57b85a97933a1d984f6e484b4021c800.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57b85a97933a1d984f6e484b4021c800.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d92faa63f0f0b144600e077009eb956e.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6c1756b564bf1d998d8179637011c88.png)
(2)若函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23980be9e2a5c9b855d58cee4b5b860e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
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3 . 已知
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eeda28e0ca073c53df10772c21557a04.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5695ad8af87b64bc152cf137ed4f5b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fabd534a0745c177bee146f0f3698721.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eeda28e0ca073c53df10772c21557a04.png)
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4 . 若
(
,
为虚数单位),则
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3374766afab14ecbd375159804126c40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10bbdef421c976962a270a2beabbad91.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a7035cd4adda5d72a9fc9f9fda75995.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
A.1 | B.![]() | C.5 | D.2 |
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5 . 在给出的下列命题中,正确的是( )
A.设![]() ![]() ![]() |
B.若向量![]() ![]() ![]() ![]() ![]() ![]() |
C.若![]() ![]() ![]() ![]() |
D.已知平面向量![]() ![]() ![]() ![]() ![]() ![]() |
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6 . 对任意的
,
恒成立,则
的取值范围为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66692ec49a458f9e48c7315d03dfc37b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/697da80270be67c88c6f742a75457d4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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7 . 设
,
,
,则三者的大小关系为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ef2a45773db8d347f0cfa4e4fca7fd5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd1cb90da3fcff90e3a6ad70765b7b88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca87d157b38f2aa01be2a889915cd3b6.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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8 . 已知数列
满足:
,且
.设
的前
项和为
,
.
(1)证明:
是等差数列;
(2)求
;
(3)若不等式
对
恒成立,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6188b06e1fb902ffa4441f45fb7b91ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f0a53b6755b419e78cb64cc193ce826.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/357cf82e1f23d4ce922990a6343407ef.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(3)若不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1385183cce8491fa911c1bd33d5ebbe0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37a59558292ad6b3d0978bfd7484990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
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9 . 已知函数
,直线
与曲线
,
都相切.
(1)求实数
的值;
(2)记
,求
的最值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f472deb981bf0d55714fdfdd8a43b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30ed86b27f8250f78ca31d5859c15254.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3897bf276a0b6c2121917d39b369df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/990b6dc6b90ee98d5a95e1518bbd61b1.png)
(1)求实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632244ea6931507f8656e1cc3437d392.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c5b648b3a4cbd6faee5743bec7ae4aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f97306ebc03780c60c20bf14364ab6.png)
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10 . 设实系数一元二次方程
①,有两根
,
则方程可变形为
,展开得
②,
比较①②可以得到![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71e360b7ba27dfc3e5d401027d5bd8a5.png)
这表明,任何一个一元二次方程的根与系数的关系为:两个根的和等于一次项系数与二次项系数的比的相反数,两个根的积等于常数项与二次项系数的比.这就是我们熟知的一元二次方程的韦达定理.
事实上,与二次方程类似,一元三次方程也有韦达定理.
设方程
有三个根
,则有
③
(1)证明公式③,即一元三次方程的韦达定理;
(2)已知函数
恰有两个零点.
(i)求证:
的其中一个零点大于0,另一个零点大于
且小于0;
(ii)求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c3f3db6b7c682450309a6ccba5ac5a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ce7ae90d808f05e86ea063238e4b2f9.png)
则方程可变形为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/455d33fcfd9a59d6b374e9d25888cd2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e42b42152492cbdfec62c7a02be4055.png)
比较①②可以得到
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71e360b7ba27dfc3e5d401027d5bd8a5.png)
这表明,任何一个一元二次方程的根与系数的关系为:两个根的和等于一次项系数与二次项系数的比的相反数,两个根的积等于常数项与二次项系数的比.这就是我们熟知的一元二次方程的韦达定理.
事实上,与二次方程类似,一元三次方程也有韦达定理.
设方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ddc5e3c2c7c6f4d2d0ab396b65679a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05b8ec9d4206ea66a02de5c4a1e1e911.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb8d75a2417827b2c5b09ba9385fe252.png)
(1)证明公式③,即一元三次方程的韦达定理;
(2)已知函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2b5e4746c2bd0afb279630698afd3a0.png)
(i)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d275fbb3ee5cd1177ca5a2ceecbbef0f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
(ii)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20d6fc9b90f370fbb27552876b650f8f.png)
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