已知 a∈R,i 为虚数单位。若复数 z=a−i1+i 是纯虚数.则a的值为( ）

题干

已知 a∈R,i 为虚数单位。若复数 z=

a

−

i

1

+

i

是纯虚数.则a的值为( ）

A：-1

B：0

C：1

D：2

上一题下一题 0.0难度选择题更新时间:2017-06-07 09:19:21

C

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