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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता ११ वी

Express the following in the form of a + ib, a, b∈R i = −1. State the values of a and b: (2 + 3i)(2 – 3i)

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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:

(2 + 3i)(2 – 3i)

बेरीज
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उत्तर

(2 + 3i)(2 – 3i) = 4 – 9i2

= 4 – 9(– 1)    ...[∵ i2 = – 1]

= 4 + 9

= 13

∴ (2 + 3i)(2 – 3i) = 13 + 0i

∴ a = 13 and b = 0

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

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