已知向量与的夹角为120°.若向量c= + .且c⊥.则值为 【
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题目列表(包括答案和解析)
已知向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/0.png)
与
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/1.png)
的夹角为120°,若向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/2.png)
,且
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/3.png)
⊥
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/4.png)
,则
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/5.png)
=( )
A.2
B.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/6.png)
C.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/7.png)
D.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131024184322036168566/SYS201310241843220361685001_ST/8.png)
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已知向量
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/0.png)
与向量
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/1.png)
的夹角为120
,若向量
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/2.png)
且
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/3.png)
,则
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/4.png)
的值为( )
A.2
B.
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/5.png)
C.
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/6.png)
D.
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202113011544762547/SYS201312021130115447625001_ST/7.png)
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已知向量
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/0.png)
与向量
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/1.png)
的夹角为120
,若向量
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/2.png)
且
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/3.png)
,则
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/4.png)
的值为( )
A.2
B.
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/5.png)
C.
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/6.png)
D.
![](http://thumb.zyjl.cn//pic6/res/gzsx/web/STSource/20131202112700331000312/SYS201312021127003310003007_ST/7.png)
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已知向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/0.png)
与向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/1.png)
的夹角为120
,若向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/2.png)
且
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/3.png)
,则
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/4.png)
的值为( )
A.2
B.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/5.png)
C.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/6.png)
D.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103102145709541017/SYS201311031021457095410001_ST/7.png)
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已知向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/0.png)
与向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/1.png)
的夹角为120
,若向量
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/2.png)
且
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/3.png)
,则
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/4.png)
的值为( )
A.2
B.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/5.png)
C.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/6.png)
D.
![](http://thumb.zyjl.cn/pic6/res/gzsx/web/STSource/20131103101729077540301/SYS201311031017290775403007_ST/7.png)
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