Find (3 + 4i)/(1 + 2i):
A2 + 2i
B11/5 - 2i/5
C(11 - 2i)/5
D1 + i
Answer & Solution
Correct answer: C. (11 - 2i)/5
Multiply numerator and denominator by conjugate of denominator: (3 + 4i)(1 - 2i)/((1 + 2i)(1 - 2i)) = (3 - 6i + 4i - 8i²)/(1 + 4) = (3 - 2i + 8)/5 = (11 - 2i)/5.
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