名校
解题方法
1 . 记
的内角
所对的边分别为
,已知
.
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e717c243991f038d7bc21a0fdad985b.png)
(2)若
的面积
,求
的最大值,并证明:当
取最大值时,
为直角三角形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce7af7c5df749c6fa9bbe87faa72c66d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88f2599ca8b6b683e57a82699c8b1ebb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55abde5108e7846f496584016ce82286.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e717c243991f038d7bc21a0fdad985b.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3a88d9c428cc72bdf012746e2781a64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
2022-12-06更新
|
756次组卷
|
3卷引用:安徽省皖优联盟2022-2023学年高三上学期12月第二次阶段性联考数学试题
名校
解题方法
2 . 数列
的前
项和为
,且
,数列
满足
,
.
(1)求数列
的通项公式;
(2)求证:数列
是等比数列;
(3)设数列
满足
,其前
项和为
,证明:
.
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22261e0f98252e0ab47b78378025e874.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/385275d29d8c8a7841eaeaa3dfab2cdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/760183e852fc753187257bbda7a5f1f9.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求证:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e3f946894e21775f9d2b4219ed627eb.png)
(3)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8b3c6bf8122b705ecfeb93b543bf93e.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/c02e80983b88cdf6b540502816c87d13.png)
您最近一年使用:0次
2020-10-31更新
|
5897次组卷
|
10卷引用:广东省广州市荔湾区2019-2020学年高二上学期期末数学试题
广东省广州市荔湾区2019-2020学年高二上学期期末数学试题广东省广州市八区2019-2020学年高二上学期期末教学质量监测数学试题广东省广州市白云区2019-2020学年高二上学期期末教学质量检测数学试题广东省广州市海珠区2019-2020学年高二上学期期末联考数学试题(已下线)考点12+等比数列-2020-2021学年【补习教材·寒假作业】高二数学(人教B版2019)黑龙江农垦建三江管理局第一高级中学2020-2021学年高三上学期12月月考数学(理)试题江西省贵溪市实验中学2020-2021学年高一3月第一次月考数学试题(已下线)专题4.3 等比数列-2020-2021学年高二数学同步培优专练(人教A版2019选择性必修第二册)(已下线)考点23 已知递推公式求同通项公式求数列的通项公式-备战2022年高考数学(文)一轮复习考点帮天津市和平区2022-2023学年高二上学期期末数学试题
12-13高二下·河南郑州·期中
3 . 在数列
中,
,且
.
(Ⅰ) 求
,猜想
的表达式,并加以证明;
(Ⅱ)设
,求证:对任意的自然数
都有
.
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/816b1d3a0bd14a20ad9586d3a8759368.png)
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/e24dc164a07e4c17889fa6d9e37c8970.png)
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/b0626ee83e62454aac8a6ed55d2101a4.png)
(Ⅰ) 求
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/3ac0bcdf79a94a7d9f12369f88a468b1.png)
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/dd30fa8c3ccf412aacf251ce256b4856.png)
(Ⅱ)设
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/f2f7b45d791b4b21836ef23ef4a77509.png)
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/0af3ff25019946b4973b987d16cbdeb6.png)
![](https://img.xkw.com/dksih/QBM/2013/5/27/1571229901840384/1571229907558400/STEM/9b2c94d402b44d9487397a9d37f8475a.png)
您最近一年使用:0次
名校
解题方法
4 . 在
中,角A,B,C所对的边分别为a,b,c,且
.
(1)证明:
为等腰三角形.
(2)若D是边BC的中点,
,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2818bff73d7e297bfbcda3d22d1a153.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)若D是边BC的中点,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb9af00d442a5c693c970f30efcc916f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
2024-06-11更新
|
1276次组卷
|
3卷引用:广西柳州市第一中学2023-2024学年高二下学期阶段性期中考试数学试题
23-24高二下·全国·课前预习
5 . 等差中项
(1)条件:如果
成等差数列.
(2)结论:那么
叫做
与
的等差中项.
(3)满足的关系式是________
温警提醒(1)任意两个实数都有等差中项.
(2)应用等差中项法也可证明一个数列为等差数列,即
为等差数列.
(1)条件:如果
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bf6726a4207c053c937cf221120dea1.png)
(2)结论:那么
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
(3)满足的关系式是
温警提醒(1)任意两个实数都有等差中项.
(2)应用等差中项法也可证明一个数列为等差数列,即
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aa511f5869c3ac911876fc9af0f51b1.png)
您最近一年使用:0次
6 . 如图,在山脚
测得山顶
的仰角为
,沿倾斜角为
的斜坡向上走
米到
,在
出测得山顶
得仰角为
,
,求坡面的坡比.(坡比是坡面的垂直高度与水平宽度的比值)
(2)求证;山高
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f435efcc7869eec21bdba1ed81dc3f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a3f9f6f08449a598c3a4e156bdcec45.png)
(2)求证;山高
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1582059edd9bd52b77b5f8a97c2039a.png)
您最近一年使用:0次
7 . 在中国,周朝时期的商高提出了“勾三股四弦五”的勾股定理的特例.在西方,最早提出并证明此定理的为公元前6世纪古希腊的毕达哥拉斯学派,他们用演绎法证明了直角三角形斜边平方等于两直角边平方之和.若一个直角三角形的斜边长等于6,则这个直角三角形周长的最大值为( )
A.![]() | B.12 | C.![]() | D.![]() |
您最近一年使用:0次
8 . 余弦定理是揭示三角形边角关系的重要定理,也是在勾股定理的基础上,增加了角度要素而成.而对三角形的边赋予方向,这些边就成了向量,向量与三角形的知识有着高度的结合.已知
,
,
分别为
内角
,
,
的对边:
(1)请用向量方法证明余弦定理
;
(2)若
,其中
为
边上的中线,求
的长度.
![](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/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.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/c5db41a1f31d6baee7c69990811edb9f.png)
(1)请用向量方法证明余弦定理
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34369422d71dd95c61cdd1b8245d7b6c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48897a577999a24e15e8645e7b23e592.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
2023-06-11更新
|
633次组卷
|
4卷引用:黑龙江省大庆市大庆铁人中学2022-2023学年高一下学期期中数学试题
23-24高二上·全国·课后作业
9 . 已知
,
是项数相同的数列.
(1)若数列
是公差为d的等差数列,数列
满足
,证明数列
是等比数列;
(2)若数列
是公比为q的正项等比数列,数列
满足
,证明数列
是等差数列.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a601ea5db825ae0d1dc6a4b3cad06b03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f4a57cc10613c6b261ac3a8649cbdaf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
您最近一年使用:0次
10 . 证明余弦定理:在
中,角A,B,C的对边为a,b,c,则
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34369422d71dd95c61cdd1b8245d7b6c.png)
您最近一年使用:0次
2023-07-08更新
|
377次组卷
|
2卷引用:广东省湛江市2022-2023学年高一下学期期末数学试题