Multiply (2 + 3i) by (1 + 2i).
A8 + 7i
B-4 - i
C-4 + 7i
D2 + 6i
Answer & Solution
Correct answer: C. -4 + 7i
Expanding gives 2 + 4i + 3i + 6i^2, and with i^2 = -1 this becomes -4 + 7i.
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