复数（2+i）i的虚部为______．_爱下问搜题

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问题填空题

复数（2+i）i的虚部为______．

答案

（2+i）i=-1+2i

由复数的概念可得：

虚部为2

故答案为：2

选择题

—Where are her books?
—________.

A. Yes, it is
B. No, they aren't
C. I don't know
D. They're her books

名词解释

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