1 . 若
,
,且
,则下列不等式一定成立的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bb78d20cf8bb76cd3cbe6275ffa4053.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1de5fcd3122443699a9f574a8396b70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/574b3c0cdd4e1c6f3c77d43dc7e0603f.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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2 . 一艘海轮从A出发,沿北偏东
的方向航行
后到达海岛B,然后从B出发,沿北偏东
的方向航行2
到达海岛C.
(2)如果下次航行直接从A出发到达C,应沿什么方向航行多少
?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a4c9b697e3df2b5469b71d3b5e47a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77cd0c83421fe4705e64c64567f1f76a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76c12e76fbd84eeec721386bd3b04cc4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c79c4c40ca54ace5faa8ed6298f98614.png)
(2)如果下次航行直接从A出发到达C,应沿什么方向航行多少
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c79c4c40ca54ace5faa8ed6298f98614.png)
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3 . 在
中,角A,B,C所对的边分别为a,b,c,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c22869d8d645863b9955c9420335db5b.png)
(1)求角A;
(2)若
,
,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c22869d8d645863b9955c9420335db5b.png)
(1)求角A;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03837b3769eda7f0d3804cc5ad4a6d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/413f9851aad373d782ae62b308f1de85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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4 . 已知角A,B,C是三角形ABC的三个内角,下列结论一定成立的有( )
A.![]() | B.![]() |
C.若![]() ![]() | D.若![]() ![]() |
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5 . 在
中,
,
,
的对边分别为
,
,
,若
,则
的形状是( )
![](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)
![](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/a1952011b53d8a859e295aadc91346cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
A.等腰直角三角形 | B.等腰三角形或直角三角形 |
C.直角三角形 | D.等腰三角形 |
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名校
解题方法
6 . 已知等比数列
满足
,
,则其前
项和![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04c2864e2ec3416cc4c081ac1f71a0af.png)
___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92e9d3644920a6654c41de61b7f3636d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51edb7027369b194443909607470afec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04c2864e2ec3416cc4c081ac1f71a0af.png)
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解题方法
7 . 古希腊的数学家海伦在其著作《测地术》中给出了由三角形的三边长a,b,c计算三角形面积的公式:
,这个公式常称为海伦公式,其中,
.我国南宋著名数学家秦九韶在《数书九章》中给出了由三角形的三边长a,b,c计算三角形面积的公式:
,这个公式常称为“三斜求积”公式.
(1)已知
的三条边分别为
,求
的面积;
(2)利用题中所给信息,证明三角形的面积公式
;
(3)在
中,
,求
面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/684c13a2cea962fb204256ca433a4d58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71d788614f1841b4943b30fe6fd1eff3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ad209824da2aadcf7b5479de68187cc.png)
(1)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51ed8dab1f54de9e1fc65fb53600610c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)利用题中所给信息,证明三角形的面积公式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/634fdb49ecc32befaf9ac4ce84ae5a37.png)
(3)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b0eba33aa912c5ce4be622945b0243c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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解题方法
8 . 在锐角
中,角
,
,
的对边分别为
,
,
,已知
.
(1)求
;
(2)若
的面积为
,求
,
;
(3)若
,求
周长的取值范围.
![](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)
![](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/3de9ff601d4e299c50cd2fc7c6923087.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c822e13da88844e7dcc02ecd4ec55e52.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adbd3e8cf8325999cde03adf845d3dd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6de1d395e6c48c0676a1488a299479d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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9 . 远赴仙境惊鸿宴,一睹人间盛世颜.位于河南洛阳的老君山群山竞秀,拔地通天.一位同学在领略老君山的美景时,用无人机测量了其中一座小山的海拔与该山最高处的古塔AB的塔高.如图,无人机的航线与塔AB在同一铅直平面内,无人机飞行的海拔高度为
,在
处测得塔底
(即小山的最高处)的俯角为
,塔顶
的俯角为
,向山顶方向沿水平线
飞行
到达
处时,测得塔底
的俯角为
,则该座小山的海拔为________
;古塔AB的塔高为________ m.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22c5729584c8dce7264e11704c61e199.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30c20e88a33043f4279fff360c81006e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/996bf3d35b6763cbc1a423b13a9df2dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f631cfdf4666db95beb923072ced8d95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79fb11b8c808bb9d9a8e1f4c53cddd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e15e00f40396e914d1d9955bd7785f1f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/24/ebd9999d-0d19-4dca-aa96-d7c651fdb356.png?resizew=162)
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解题方法
10 . 在
中,内角A,B,C的对边分别为a,b,c,下列说法中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
A.若![]() ![]() |
B.若![]() ![]() |
C.若![]() ![]() |
D.若![]() ![]() |
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