Engineering Board Exam Reviewer · Complex Numbers: Operations · easy

Simplify (3+2i)(4-5i).

1. 22 - 7i
2. 2 - 7i
3. 12 - 10i
4. 22 + 7i

Answer

A. 22 - 7i

Solution

(3+2i)(4-5i)=12-15i+8i-10i2=12-7i+10=22-7i.

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