# calculus

posted by .

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 -

They want to know the:

remaining zeros of f

• calculus -

complex roots come in pairs, so the others must be -i and 9-i.

Algebra I, I believe.

• calculus -

The reason they specify real coefficeints is so that you know the complex roots come in conjugate pairs. Otherwise, it is not true, since

(x-3)(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.

## Similar Questions

1. ### pre-calculus

information is given about the polynomial f(x) whose coefficients are real numbers. find the real zeros of f: degree 4; zeros: i, 3+i
2. ### Pre-calculus

Sorry i wrote the last question wrong, it was suppose to be written as: information is given about the polynomial f(x) whose coefficients are real numbers. find the remaining zeros of f: degree 4; zeros: i, 3+i
3. ### Math

Use the given information about a polynomial whose coefficients are real numbers to find the remaining zeros of the polynomial. Degree: 6 Zeros: -6 + 13i^3, -8 + s^2i, -3 - 4i
4. ### pre calculus

use given info about a polynomial whose coefficients are real numbers to find the remaining zeros. Degree: 6 so I know there's at least 6 zeros:-5-isqrt7, 13 + 2ni, -5 - 3i (where n is a real number) any ideas?
5. ### algebra

Use the given information about a polynomial whose coefficients are real numbers to find the remaining zeros. degree: 6 Zeros: -8 + 11x(can't put this sign in looks like ii with slash over)i, -7 + 17i, 16 - isqrt 2
6. ### college algebra--need help please!!

information is given about a polynomial f(x)whose coefficients are real numbers. Find the remaining zeros of f. degree:5, zeros: -6, 6-i please help and show all work.