What Is The Sum Of The Roots Of The Polynomial Shown F(x)= 3x^3+12x^2+3x-18

Question

directrix · Answer

There's a theorem about the sum and products of roots of polynomials that I would like to post if I can find it on the Internet. I have it in a book and would have to scan it.
Just a second.

directrix · Answer

3x^3+12x^2+3x-18

directrix · Answer

The sum of the roots is the following:  Negative a sub n-1 coefficient divided by a sub n coefficient

directrix · Answer

In this problem, 12 is the a sub n-1 coefficient.

Also, 3 is the a sub n coefficient. 

The coefficients are systematically named to coordinate with the exponents of the variables with which the coefficient appear.

directrix · Answer

All that boils down to  - 12/3 = ?

I will get this theorem scanned and posted because it gives not only the sum of roots but the products as well. Powerful.

directrix · Answer

@Gems820    Question?

anonymous · Answer

Thank You @Directrix

directrix · Answer

Glad to help. Attached is that theorem.