(1)
中,
,
,
,且
,判断
的形状;
(2)四边形
中,
,
,
,
,且
,判断四边形
的形状.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93f3d3d11e628c23ca94e505530520d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44f0589298e015be01e2420268262f55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/692be13a48cee7226f475c6a0bb94552.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4614ceb12fa5ac7e317053804b9f940a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac265febbf99dccf51aa0a2253e61f1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3b29e4bb5df725a1863db727e78a91b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73040622cd5efe89a46a6e65f094dfcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a8d2d0c27bcb35494e1817778f620d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69ef7b6b005b9016b7da41b748e1c77e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
更新时间:2020-06-26 16:20:59
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图所示,在
中,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2021/4/7/2694799267225600/2787496447664128/STEM/b6d53a5f-3d33-4eca-afb6-497fc8778726.png?resizew=193)
(1)试用向量
,
来表示
,
;
(2)
交
于
点,若
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5138a9f70d5e8b0580e30fef6eb7baef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/812b4f3e7971cdde034d41202967b448.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d64fe2af577d88ef2000744582700957.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e7a93a1399ff7a2bde342652479241b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3b54aa2b7f9adf409f0ce8e00615432.png)
![](https://img.xkw.com/dksih/QBM/2021/4/7/2694799267225600/2787496447664128/STEM/b6d53a5f-3d33-4eca-afb6-497fc8778726.png?resizew=193)
(1)试用向量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb80eb942aafb194fadc473776f35b1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/433b94c39737727e53468df419d8314a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1597427446eb525d66724e2024476c45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/888afd002858f23a84a8755a002bed7a.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3533837e3d08c461dea031a44e5424d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ab9468a49f875255a838d1fe65add02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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【推荐2】如图,四边形ABCD是平行四边形,点E,F分别为CD,AD的中点
(1)以
,
为基底,分别表示向量
,
;
(2)以
,
为基底,表示向量
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/7/322000f6-8658-4886-bf9c-18d2ff769b3e.png?resizew=202)
(1)以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abcb5d89b04570ceda2c29e11cb27a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/304a7f07db2ec637baadf8f0ab91c85c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d021a5c98388463d577675e58068aa7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba7d3a0680780aaf4549c447fe8dfe9f.png)
(2)以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d021a5c98388463d577675e58068aa7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba7d3a0680780aaf4549c447fe8dfe9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af5f1b06a56fc382feed28e01f1ad102.png)
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适中
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解题方法
【推荐1】已知
,
是两个不共线的非零向量,
,
,且
与
的夹角是120º,
(1)求
的大小;
(2)记
,
,
,若向量
与
的夹角为锐角,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb80eb942aafb194fadc473776f35b1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/433b94c39737727e53468df419d8314a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f18996bd00253c3ad9f91780103affb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df42687a73cb92e92a3cb6e54f1edb15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb80eb942aafb194fadc473776f35b1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/433b94c39737727e53468df419d8314a.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3eebc03129bad1dfc7d85ee62145cc7b.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91a9cb32a25c2a8bb99f75633b4cd5ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ece7ff6a365f1489165649106b9a1010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfb70dc862df380c7ed892e0e95ee492.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be64d59ac6538a0f4d79fb825e082081.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d792a2aa25763e14cc2863be3887000.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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解答题-问答题
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适中
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解题方法
【推荐2】已知向量
,
,
,且
.
(1)求
的值;
(2)求
与
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/252c8b84033aef7b05b220257d09f67a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fe58817538d3432f490b5f7c7d95c30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8534bdbec5f078cb39f98f95cd487b34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa5aa846a5b7c96fe2ce665eb1ea5f0e.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb80eb942aafb194fadc473776f35b1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb573cc0f30d5c32cdad1510793f0e7b.png)
您最近一年使用:0次