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Answer the following: Simplify the following and express in the form a + ib: 5+7i4+3i+5+7i4-3i

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Question

Answer the following:

Simplify the following and express in the form a + ib:

`(5 + 7"i")/(4 + 3"i") + (5 + 7"i")/(4 - 3"i")`

Sum
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Solution

`(5 + 7"i")/(4 + 3"i") + (5 + 7"i")/(4 - 3"i")`

= `((5 + 7"i")(4 - 3"i") + (5 + 7"i")(4 + 3"i"))/((4 + 3"i")(4 - 3"i"))`

= `((5 + 7"i")(4 - 3"i" + 4 + 3"i"))/(16 - 9"i"^2)`

= `((5 + 7"i")(8))/(16 + 9)`   ...[∵ i2 = – 1]

= `(40 + 56"i")/25`

= `40/25 + 56/25"i"`,

which is of the form a + bi.

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Chapter 1: Complex Numbers - Miscellaneous Exercise 1.2 [Page 21]

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Balbharati Mathematics and Statistics (Arts and Science) Part 2 [English] Standard 11 Maharashtra State Board
Chapter 1 Complex Numbers
Miscellaneous Exercise 1.2 | Q II. (1) (x) | Page 21

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