# Homework Help: Another Complex root problem

1. Oct 24, 2007

### Corkery

1. The problem statement, all variables and given/known data
State the number of complex roots and then identify what the roots are.

Equation:
18x^2 + 3x -1 = 0

2. Relevant equations

3. The attempt at a solution
There are 2 complex roots.

Okay. So I cant factor anything out of the equation and when you try to factor it by hand it doesnt work. So what should I do? quadratic formula? Please help me.

2. Oct 24, 2007

### cristo

Staff Emeritus
I would use the quadratic formula, yes.

3. Oct 24, 2007

### Dick

4. Oct 24, 2007

### Corkery

thanks.

5. Oct 25, 2007

### bala.l

You can factor out the polynomial as
18x^2 + 6x - 3x - 1
= 6x(3x+1) - (3x+1)
= (6x-1) (3x+1)

6. Oct 25, 2007

### HallsofIvy

I wish you would stop titling these "complex roots". So far none of the problems you have posted has had complex roots!

7. Oct 25, 2007

### Corkery

oh sorry. In my book that section says "complex roots" but next time I will try my best to label it appropriately.