SOLUTION: Determine without converting the form and leave answer in the form of a+bi (2-i)(3+4i) / ì-3

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Question 1180448: Determine without converting the form and leave answer in the form of a+bi
(2-i)(3+4i) / ì-3
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Determine without converting the form and leave answer in the form of a+bi
%28%282-i%29%283%2B4i%29%29%2F%28i%2B3%29
same as
%28%282-i%29%283%2B4i%29%29%2F%283%2Bi%29
FOIL the numerator
%286%2B8i-3i-4%28i%5E2%29%29%2F%283%2Bi%29 = %286%2B5i-4%28-1%29%29%2F%283%2Bi%29 = %286%2B5i%2B4%29%2F%283%2Bi%29 = %2810%2B5i%29%2F%283%2Bi%29
multiply by the conjugate of the denominator over itself
%2810%2B5i%29%2F%283%2Bi%29 *%283-i%29%2F%283-i%29 = %28%2810%2B5i%29%283-i%29%29%2F%28%283%2Bi%29%283-i%29%29 = %2830-10i%2B15i-5%28i%5E2%29%29%2F%289-i%5E2%29 = %2830%2B5i-5%28-1%29%29%2F%289-%28-1%29%29 = %2830%2B5i%2B5%29%2F10 =
%2835%2B5i%29%2F10
cancel out 5
%287%2Bi%29%2F2 or (3.5 + .5i)