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Express the given complex number in the form a + ib: 3(7 + i7) + i(7 + i7)

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Question

Express the given complex number in the form a + ib: 3(7 + i7) + i(7 + i7)

Sum
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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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Chapter 4: Complex Numbers and Quadratic Equations - EXERCISE 4.1 [Page 83]

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NCERT Mathematics [English] Class 11
Chapter 4 Complex Numbers and Quadratic Equations
EXERCISE 4.1 | Q 4. | Page 83

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