SOLUTION: 12+18i ________ 3-i

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Question 1004959: 12+18i
________
3-i
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply top and bottom by 3%2Bi

Note: 3%2Bi is the conjugate of 3-i (the denominator)

%2812%2B18i%29%2F%283-i%29

%28%2812%2B18i%29%2F%283-i%29%29%2A%28%283%2Bi%29%2F%283%2Bi%29%29

%28%2812%2B18i%29%2A%283%2Bi%29%29%2F%28%283-i%29%2A%283%2Bi%29%29

%2836%2B12i%2B54i%2B18i%5E2%29%2F%289%2B3i-3i-i%5E2%29

%2836%2B12i%2B54i%2B18%28-1%29%29%2F%289%2B3i-3i-%28-1%29%29

%2836%2B12i%2B54i-18%29%2F%289%2B3i-3i%2B1%29

%2818%2B66i%29%2F%2810%29

18%2F10%2B%2866i%29%2F10

9%2F5%2B%2833%2F5%29i

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So, %2812%2B18i%29%2F%283-i%29=9%2F5%2B%2833%2F5%29i

9%2F5%2B%2833%2F5%29i is in standard form a%2Bbi where a=9%2F5 and b=33%2F5