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Question
Find a and b if (a – b) + (a + b)i = a + 5i
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Solution
(a – b) + (a + b)i = a + 5i
Equating the real and imaginary parts separately, we get,
a – b = a ...(1)
and a + b = 5 ...(2)
From (1), – b = 0
∴ b = 0
∴ from (2), a + 0 = 5
∴ a = 5
Hence, a = 5, b = 0.
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