SOLUTION: 5+2i divided by -7i+3

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Question 31896: 5+2i divided by -7i+3
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
+%28+%285%2B2i%29%2F%283-7i%29+%29%2A%28+%283%2B7i%29%2F%283%2B7i%29+%29+

Now i shall do ALL the working, although the whole point of choosing 3+7i was that we can write the denominator straight away as: (9+49) thus avoiding all that unnecessary work:

+%28%285%2B2i%29%283%2B7i%29%29%2F%28%283-7i%29%283%2B7i%29%29+
+%2815%2B35i%2B6i%2B14i%5E2%29%2F%289%2B21i-21i-49i%5E2%29+
+%2815%2B41i%2B14i%5E2%29%2F%289-49i%5E2%29+

now, since +i%5E2+=+-1+, we get:
+%2815%2B41i%2B14%28-1%29%29%2F%289-49%28-1%29%29+
+%2815%2B41i-14%29%2F%289%2B49%29+
+%281%2B41i%29%2F%2858%29+

jon.