SOLUTION: What is the product of the complex numbers (3+i) and (3-i)? A) 8 B) 10 C) 9-i D) 10-6i

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Question 395851: What is the product of the complex numbers (3+i) and (3-i)?
A) 8
B) 10
C) 9-i
D) 10-6i
Found 2 solutions by Edwin McCravy, stanbon:
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
(3 + i)(3 - i) = 9 - 3i + 3i - i² = 9 - i² = 9 - (-1)² = 9 - 1 = 8

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What is the product of the complex numbers
(3+i) and (3-i)
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Use FOIL:
F: 3*3 = 9
O: 3*-i = -3i
I; 3*i = 3i
L: i*-i = i^4 = 1
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Combine to get 9+1 = 10
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Cheers,
Stan H.
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A) 8
B) 10
C) 9-i
D) 10-6i