SOLUTION: (6-9i)2

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Question 401027: (6-9i)2
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
I assume the 2 at the end is an exponent. Please use the "^" character to indicate exponents, like this:
(6-9i)^2
Tutors are more likely to help if the problem is clear.

To multiply this we can use FOIL on (6-9i)(6-9i), or we can use the %28a-b%29%5E2+=+a%5E2-2ab%2Bb%5E2 pattern with "a" being 6 and "b" being 9i. I prefer using the pattern:
%286%29%5E2-2%286%29%289i%29%2B%289i%29%5E2
which simplifies to:
36-108i%2B81i%5E2
i = sqrt%28-1%29 so i%5E2+=+-1. Substituting -1 for i%5E2 we get:
36-108i+81(-1)
which simplifies as follows:
36-108i+(-81)
-45+108i

P.S. Thanks for your thank you note. It is nice to be appreciated!

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which would make it very difficult for us to work something out with which we could both be happy.

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