2. $(5$ 分 $)(1+i)(2-i)=(\quad)$
Gaokao · Math · previous-year question
- A.$-3-i$
- B.$-3+i$
- C.$3-i$
- D.$3+i$correct
Answer
D. $3+i$
Explanation
解: $(1+i)(2-i)=3+i$. 故选: D.
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