SOLUTION: If (1-i)(3+i) = a + bi. What is the value of a + b

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Question 1198995: If (1-i)(3+i) = a + bi. What is the value of a + b
Answer by MathLover1(20850) About Me  (Show Source):
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If %281-i%29%283%2Bi%29+=+a+%2B+bi. What is the value of a+%2B+b

%281-i%29%283%2Bi%29+=+a+%2B+bi
1%2A3%2B1%2Ai-i%2A3-i%2Ai+=+a+%2B+bi
3%2Bi-3i-i%5E2+=+a+%2B+bi
3-2i-%28-1%29+=+a+%2B+bi
3-2i%2B1+=+a+%2B+bi
4+-+2i=+a+%2B+bi
=>a=4,+b=2
the value of+a+%2B+b=4%2B2=6