1 . 从①
;②
;③
, 这三个条件中任选一个, 补充在下面问题中, 并加以解答.
在
中,三边
分别是角
的对边, 若______.
(1)求C;
(2)若
,求
的面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d8447a2411972b1375712e3c28cdca6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65d983612b3c1977916dd721d3413bce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50ad4300ec11d8da30369d44a3cdf07d.png)
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e5ba3badffe942dcfb60da88629e7b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e70100bd019ce2be544ccd266318b0bd.png)
(1)求C;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6de1d395e6c48c0676a1488a299479d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bf59f210a4f3916022847a4fd61b6ed.png)
您最近一年使用:0次
解题方法
2 . 在正方体
中,面对角线
,
上各有一个动点
,
,使得直线
平面
.
,
为对角线
,
的中点,
为
的中点时,证明:平面
平面
;
(2)当正方体棱长为2时,求线段
长度的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e539f26ed5e0b20ff7220559324869a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e539f26ed5e0b20ff7220559324869a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39e901fef303d9063677b8885702a967.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
(2)当正方体棱长为2时,求线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
您最近一年使用:0次
解题方法
3 . 已知复数
,
,
是虚数单位.
(1)若复数
是纯虚数,求
的值;
(2)若复数
在复平面内对应的点在第三象限,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11c45a5d9937039ab2ca54709515dcab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40e72f6b2ef3329828cb8fc873eeba7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a7035cd4adda5d72a9fc9f9fda75995.png)
(1)若复数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(2)若复数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
4 . 如图,在平行四边形
中,
为
的中点,
为
上一点且满足
,
,
.
,
表示
,
;
(2)若
,
,求向量
,
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64f978a9608d6e9d5c0c67fceb5e57c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f3adc4ed291596abf3bb93ae7a075d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/184359fe3cadc363cf4ebe586c2b3db4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba7d3a0680780aaf4549c447fe8dfe9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b95278c67ae9f17b640caab6c8ec418c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa1466856bf2570685d3629c1f813748.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de745f4a313e835454881b20c7fabeb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba7d3a0680780aaf4549c447fe8dfe9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b95278c67ae9f17b640caab6c8ec418c.png)
您最近一年使用:0次
解题方法
5 . 在
中,角
,
,
的对边分别为
,
,
.若
,
.
(1)若
为锐角三角形时,求边
的取值范围;
(2)求
面积的最大值;
(3)在(1)的条件下,若
,
分别为
,
的中点,连接
,
交于点
,求
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/03837b3769eda7f0d3804cc5ad4a6d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05fccb8041c4caf53dc199b1cba2e062.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(3)在(1)的条件下,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9d529116469135597c7bf6455625d39.png)
您最近一年使用:0次
6 . 已知
中,角A,B,C对应边分别为a,b,c.
(1)求证:
;
(2)已知
.
①若
,求A;
②若
是锐角三角形,且
,求
周长的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8df60d8ae1e87ccc51be55f99b01f3b9.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b19988d792b5252222f0a7acf7ef5fd.png)
①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3578b63c5903089595bf324c809a997c.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
7 . 在平面直角坐标系中,点
为坐标原点,已知
,
,
.
(1)求向量
与
夹角的余弦值;
(2)若点
满足
,
,求点
的坐标及向量
在向量
上的投影向量的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98b2cc0d2f6d3eee9a33db83e0c0830d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8159754fa962579d7dcb79da0ba1908.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02eea25799267c0a948a6a9ffab2ffd9.png)
(1)求向量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4f605ec0729ce6d72237ad662a06862.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89265cbe3abc6b966ce8967fead448b.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8978ecc859804a7c23c2cc8c9175677.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1206fd4b58cd793401ef61fd2ff22ee3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f28b09c6074898b0bf992928336eb5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fc9656d8286c4d6fa309d6ae347c89e.png)
您最近一年使用:0次
8 . 已知
,
,函数
.
(1)求函数
的解析式及对称中心;
(2)若
,求
的值;
(3)在锐角
中,角
,
,
分别为
,
,
三边所对的角,若
,
,求
周长的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6f09dc9e7618e8ccf537e29632f4d68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f673a7fc7ccef28ce684b3b12947b40e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7aa1233d7a93113281594c41f25c7db.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c44ec7aa6a761bc92aded56ef5c69ccf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c98121b68063a3450865da0ef39ab07.png)
(3)在锐角
![](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/5742b2684d00be50a66e01c9acb6b51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a96724d332543adb6ce85c1a725ba558.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
9 . 折扇又名“纸扇”,是一种用竹木或象牙做扇骨,韧纸或者绫绢做扇面的能折叠的扇子,折扇的扇面自古以来就是文人墨客喜爱的诗画载体.图2中扇形
是图1中扇面的平面图,其中
.如图3,某书画家计划在该扇形内取一个矩形
进行绘画或书写以抒情达意,设点
为弧
的中点,扇形半径为1,
,记矩形
的面积为关于
的函数
.
的解析式,并指出当
为多大时,
最大;
(2)令
,若
在区间
上有两个零点,求实数
的取值范围;
(3)若
为扇形
中
上的一个动点,且
,其中
,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a77343ecde1c2665df291761b6563.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ff5c21185c13eae675906dabd3593c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52bdd7b8a0dcc06988320f476956f8f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4920b6731fc1580a46dad9ca40609d80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4669810732b633b60dbeaf0bf57204f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44d51992c05a557cf6058664f1f8961e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4819c39c281427826e1b3f7a4c2b720.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16d65cecaf8a3dc2953f4109c75a981e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37dd0802f896556180545ae356e90c7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa72c594ebe33496fa7b9edf1db5c7e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/febf7413b35cf2889fdb57a6b519087c.png)
您最近一年使用:0次
解题方法
10 . 已知斜三角形
.
(1)借助正切和角公式证明:
.
并充分利用你所证结论,在①②中选择一个求值:
①
,
②
;
(2)若
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(1)借助正切和角公式证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f846e5859aab52461b125a83652ec9.png)
并充分利用你所证结论,在①②中选择一个求值:
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7798db106b4bed40fd7b43a9eaeb463.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6508e636cfd77c0a0406b3fbf3b70213.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5cc19955c1f24f90d36c68aba23bebd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a30f03a31c8a873bfcf7287e45b6c6a0.png)
您最近一年使用:0次