已知
的内角A,B,C所对的边分别为a,b,c,
.
(1)求B;
(2)若点D在AC上,且
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/309f537e5bd6c092d0017bb1e4d3cc83.png)
(1)求B;
(2)若点D在AC上,且
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/417a1d5c9063a6eb4a3e6391ee44e771.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11f787941cb1abfe9bb757276b765c0b.png)
更新时间:2024-04-10 23:07:33
|
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】已知
的内角A,B,C的对边分别为a,b,c,且
.
(1)若
,
,求A;
(2)若
,求
面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1741d486796fe604cef5b7f6486459e.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f68fd85a7e024c5af7d1bc8e7a25446.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3aef40050792fd31dc042d12c0aa55d8.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3320a13248a3a1208ff6ee85c9d26f36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】在
中,内角
所对的边分别为
,满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c109fb5db5efdd7558fc14be27508f8.png)
(1)求证:
;
(2)若
为锐角三角形,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c109fb5db5efdd7558fc14be27508f8.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8904522bf844b61febddc24346f8232f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/824379180b91379b3cad7cfc3533be39.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】
中,角A,B,C的对边分别为a,b,c,且
.
(1)求证:
;
(2)若
,试求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d00c05c8a29672eab68eb17da0a52bc7.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fefb66baf2c738593be618b5895c4975.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2157af46e8e67ded9b418752a1faf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c046006255071ed05f2658cf6f9519e1.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.64)
【推荐2】在
中,
分别是角
的对边,
为
的面积,若
,且
.
(Ⅰ)求
的值;
(Ⅱ)求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f2333da32638ec636fa1e69e750ca4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a25b24bde7a2fe3760a1ada69dca68f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f18f6b95f07e84efcba743ff6aad8c85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f2333da32638ec636fa1e69e750ca4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a7dbc702617c765a573961953cc0901.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a48b5820e595211fb9106739616b38f.png)
(Ⅰ)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e6b1f3c5dbca7ec83acf8850cdd2360.png)
(Ⅱ)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】已知
分别为三角形
三个内角
的对边,且有
.
(1)求角A;
(2)若
为边
上一点,且
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/630e71b21f1009a45e0dfa038ea1aea3.png)
(1)求角A;
(2)若
![](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/c11fa1d10873d303f8633097385dcb87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dcfa3e340b3976832d450dd4ae7e7a7.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐2】设a,b,c分别为
内角A,B,C的对边,已知
,
.
(1)求A的值;
(2)若
,
,求c的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03837b3769eda7f0d3804cc5ad4a6d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/621f0f565c473d7f14a912acd2191e66.png)
(1)求A的值;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d253dd9af597ae29b98628f185eb447.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb0786732df29e599cd67cd69e5a1a5f.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐3】在
中,已知
,
,
.
(1)若
为
边上的中线,求
的长度;
(2)若
平分
,且
点在
上,求
的长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8a7b5adfcac0f46a4cd19da4ebb4a2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e899c486dc49e560fc4aca05e16835b7.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,在
中,
,
.
![](https://img.xkw.com/dksih/QBM/2022/5/1/2970155665424384/2976531131375616/STEM/db485830-307d-4679-8489-14fd33c6fb82.png?resizew=192)
(1)当
,
满足什么条件时,AC与BD互相垂直?
(2)
与
有可能相等吗?为什么?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5138a9f70d5e8b0580e30fef6eb7baef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac265febbf99dccf51aa0a2253e61f1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a44a918c7cfd942d3a53e584c26685a8.png)
![](https://img.xkw.com/dksih/QBM/2022/5/1/2970155665424384/2976531131375616/STEM/db485830-307d-4679-8489-14fd33c6fb82.png?resizew=192)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b195aa36a3c2753ebf08cb464c52ad1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc23a04cdac6439ea170e799f1c1df5.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】利用向量的数量积证明如下结论.
(1)长方形的两条对角线相等;
(2)平行四边形对角线的平方和等于四边的平方和.
(1)长方形的两条对角线相等;
(2)平行四边形对角线的平方和等于四边的平方和.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐3】如图,在平行四边形ABCD中,E点是AB的中点,F,G点分别是AD,BC的四等分点(
,
).设
,
,
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/1a5afb4f-0a4d-474c-8cd0-77213ad114b7.png?resizew=174)
(1)用
,
表示
,
;
(2)如果
,EF、EG 有什么位置关系?用向量的方法证明你的结论.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9870b92261fd2801d2a14c8dc0c4af04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8fb5c97a1eba9f96050ab44a71fea94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b536ac375a0b74e9c7efbc585f987f72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c4abd10ab43ce90743bd0f79b1f5bfc.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/1a5afb4f-0a4d-474c-8cd0-77213ad114b7.png?resizew=174)
(1)用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a92e6eba8dab638fd66831cd3a0b6d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/427fa45527d0ce469bfd060bf6f991f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1307cc4692a34308f7e534e56882b76f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f928be609ec54a597784c3b47522fc7a.png)
(2)如果
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72d3f38e6463f803de27aa303c26773e.png)
您最近一年使用:0次