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设平面向量=(1,2),=(-2,y),若∥,则|2-|等于( ) A.4 B....
设平面向量
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=(1,2),
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=(-2,y),若
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∥
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,则|2
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-
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|等于( )
A.4
B.5
C.
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D.
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考点分析:
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的图象,只需把函数y=lgx的图象上( )
A.所有点向右平移1个单位长度
B.所有点向下平移1个单位长度
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数列{a
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*)中,a
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的极小值点.
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n;
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在平面直角坐标系xOy中,经过点
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124148874596243/SYS201310251241488745962020_ST/0.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124148874596243/SYS201310251241488745962020_ST/1.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124148874596243/SYS201310251241488745962020_ST/2.png)
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共线?如果存在,求k值;如果不存在,请说明理由.
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