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Express the following in the form of a + ib, a, b∈R i = −1. State the values of a and b: (1+ i)(1− i)−1

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प्रश्न

Express the following in the form of a + ib, a, b ∈ R, i = `sqrt(−1)`. State the values of a and b:

(1 + i)(1 − i)−1 

योग
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उत्तर

(1 + i)(1 − i)−1 

= `(1 + "i")/(1 - "i")` 

= `((1 + "i")(1 + "i"))/((1 - "i")(1 + "i")`

= `(1 + 2"i" + "i"^2)/(1 - "i"^2)`

= `(1 + 2"i" - 1)/(1 - (-1))`   ...[∵ i2 = −1]

= `(2"i")/2`

= i

∴ (1 + i)(1 − i)−1 = 0 + i

∴ a = 0 and b = 1

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अध्याय 1: Complex Numbers - Exercise 1.1 [पृष्ठ ६]

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बालभारती Mathematics and Statistics 2 (Arts and Science) [English] Standard 11 Maharashtra State Board
अध्याय 1 Complex Numbers
Exercise 1.1 | Q 4. (ii) | पृष्ठ ६

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