Form a Polynomial given degree and zeros

• Oct 28th 2009, 08:22 PM
osumatt
Form a Polynomial given degree and zeros
Hello. Any help would be appreciated on showing me how to solve this problem. (Rofl)

Form a polynomial with real coefficients having a degree of 3 and zeros -5 and 1+i.
• Oct 28th 2009, 08:30 PM
mr fantastic
Quote:

Originally Posted by osumatt
Hello. Any help would be appreciated on showing me how to solve this problem. (Rofl)

Form a polynomial with real coefficients having a degree of 3 and zeros -5 and 1+i.

Factors of the required polynomial are $(z + 5)$, $(z - [1 + i])$ and $(z - [1 + i])$. Note that $(z - [1 + i])(z - [1 - i]) = (z - 1)^2 + 1 = z^2 - 2z + 2$.