SOLUTION: I need help solving a polynomial using synthetic division. (4x^3-9ix^2+5x+(8-4i))/(x-i) Thank You

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Question 600322: I need help solving a polynomial using synthetic division.
(4x^3-9ix^2+5x+(8-4i))/(x-i)
Thank You

Found 2 solutions by stanbon, Edwin McCravy:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
(4x^3-9ix^2+5x+(8-4i))/(x-i)
-----
i)....4......9i......5......(8-4i)
.......4......13i....-8.....|..9-12i
-----
Quotient: 4x^2 + 13ix - 8
Remainder: 9-12i
========================
cheers,
Stan H.

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
(4x^3-9ix^2+5x+(8-4i))/(x-i)

The other tutor's answer is wrong.

Start with this:

i | 4  -9i   5   8-4i
  |__________________   
  
Bring down the 4

i | 4  -9i   5   8-4i
  |__________________   
    4  
 
Multiply the 4 by the i gatting 4i. Write 4i above and to the 
right of the 4 that you brought down, underneath the -9i:

i | 4  -9i   5   8-4i
  |     4i           
    4

Add the -9i and the 4i getting -5i.  Write that below the line
under the 4i

i | 4  -9i   5   8-4i
  |     4i           
    4  -5i 
   
Multiply the -5i by the i and get -5i², then
replace i² by -1 and get -5(-1) or 5 and write
5 above and to the right of the -5i under the
other 5:

i | 4  -9i   5   8-4i
  |     4i   5          
    4  -5i 

Add the 5 and the 5 getting 10 and
write that at the bottom under the
5's
   
i | 4 -9i    5   8-4i
  |    4i    5       
    4 -5i   10

Multiply the 10 by the i getting 10i.
Write that above and to the right of
the 10 underneath the -4i

i | 4 -9i    5    8- 4i
  |    4i    5      10i
    4 -5i   10

Add the 8-4i and the 10i getting 8+6i.
Write that at the bottom under the +10i
 
i | 4 -9i    5    8- 4i
  |    4i    5      10i
    4 -5i   10    8+ 6i

Use the first three terms on the bottom row 
as coefficients of a quadratic equation,
then put the last number on the bottom over
the original divisor x-i

4x² - 5ix + 10 + %288%2B6i%29%2F%28x-i%29


Edwin