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若复数是纯虚数,则实数a的值为( ) A.2 B. C. D.
若复数
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231546142782392/SYS201311012315461427823002_ST/0.png)
是纯虚数,则实数a的值为( )
A.2
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231546142782392/SYS201311012315461427823002_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231546142782392/SYS201311012315461427823002_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231546142782392/SYS201311012315461427823002_ST/3.png)
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