SOLUTION: (10+i)^2 / 4-i thanks for the help!

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Question 160308: (10+i)^2 / 4-i
thanks for the help!
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
%28%2810%2Bi%29%5E2%29%2F%28%284-i%29%29
;
Foil (10+i)(10+i)
%28%28100%2B20i%2Bi%5E2%29%29%2F%28%284-i%29%29 = %28%28100%2B20i-1%29%29%2F%28%284-i%29%29 = %28%2899%2B20i%29%29%2F%28%284-i%29%29
:
Multiply by the conjugate of the denominator over itself
%28%2899%2B20i%29%29%2F%28%284-i%29%29 * %28%284%2Bi%29%29%2F%28%284%2Bi%29%29 = %28%28396%2B99i%2B80i%2B20i%5E2%29%29%2F%28%2816%2B4i-4i-i%5E2%29%29 = %28%28396%2B179i%2B20%28-1%29%29%29%2F%28%2816-i%5E2%29%29 = %28%28396%2B179i-20%29%29%2F%28%2816-%28-1%29%29%29
:
Minus a minus is a plus (denominator)
%28%28376%2B179i%29%29%2F%28%2816%2B1%29%29 = %28%28376%2B179i%29%29%2F%28%2817%29%29 = 376%2F17+%28179i%29%2F17