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Find a and b if abi = 3a − b + 12i - Mathematics and Statistics

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प्रश्न

Find a and b if abi = 3a − b + 12i

बेरीज

उत्तर

abi = 3a – b + 12i

0 + abi = (3a – b) + 12i

Equating real and imaginary parts, we get

3a – b = 0

∴ 3a = b   ...(i)

and ab = 12

∴ b = `12/"a"`   ...(ii)

Substituting b = `12/"a"` in (i), we get

3a = `12/"a"`

∴ 3a2 = 12

∴ a2 = 4

∴ a = ± 2

When a = 2, b = `12/"a" = 12/2` = 6

When a = – 2, b = `12/"a" = 12/(-2)` = – 6

∴ a = 2 and b = 6 or a = – 2 and b = – 6

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

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