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Question
Simplify the following and express in the form a + ib:
(2 + 3i)(1 – 4i)
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Solution
(2 + 3i)(1 – 4i)
= 2 – 8i + 3i – 12i2
= 2 – 5i – 12(– 1) ...[∵ i2 = – 1]
= 14 – 5i
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