http://i103.photobucket.com/albums/m...9/111001-2.jpg

I get this far, and then i get stuck..i dont know what to do...when I multiply by (X + 8i), i keep getting the wrong answer..could someone please help me? Thank you

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- Sep 28th 2007, 01:17 PMaikenfanFind Polynomial given zeros
http://i103.photobucket.com/albums/m...9/111001-2.jpg

I get this far, and then i get stuck..i dont know what to do...when I multiply by (X + 8i), i keep getting the wrong answer..could someone please help me? Thank you - Sep 28th 2007, 01:22 PMPlato
If you want

**all real coefficients**, then the complex roots must occur in conjugate pairs.

So use {-3,4,8i,-8i} four roots give four factors. - Sep 28th 2007, 01:28 PMaikenfan
Now I get

x^2 - x - 12 (x^2 - 64i^2)

Now do I multiply those together? - Sep 28th 2007, 01:57 PMPlato
- Sep 28th 2007, 02:07 PMaikenfan
x^4 - x^3 + 52x^2 - 768

- Sep 28th 2007, 02:32 PMPlato
- Sep 28th 2007, 02:59 PMaikenfan
Thank you for all of your help:)