Question 380009
1)(3+sqrt(-16))(4+sqrt(-9)) 
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= (3+4i)(4+3i)
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= 12+ 9i + 16i +12i^2
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= 12 +25i -12
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= 25i
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2)(-3+4i)^2
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= (-3+4i)(-3+4i)
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= 9 -12i -12i +16i^2
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= 9 -24i -16
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= -7-24i
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Cheers,
Stan H.