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Question
Express the given complex number in the form a + ib: 3(7 + i7) + i(7 + i7)
Solution
3(7 + i7) + i (7 + i7)
= 21 + 21i + 7i + 7i2
= 21 + 28i + 7(-1) [∵ i2 = -1]
= 21 – 7 + 28i
= 14 + 28i
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