Posted by Breanna on .
information is given about a polynomial f(x) whose coeffiecients are real numbers. Find the remaining zeros of f.
degree4, zeros i, 9+i
**I am just not getting these coefficients. I know that there has to be an easier way to learn this. Please help!!

calculus 
Breanna,
They want to know the:
remaining zeros of f 
calculus 
Steve,
complex roots come in pairs, so the others must be i and 9i.
Algebra I, I believe. 
calculus 
Steve,
The reason they specify real coefficeints is so that you know the complex roots come in conjugate pairs. Otherwise, it is not true, since
(x3)(x+i) = x^2  3x + ix  3i
= x^2 + (3+i)x  3i
which is a perfectly useful quadratic, but its coefficients are not real, so the roots do not have to come in conjugate pairs.