given that -1 is a root of the equation 2x^3-5x^2-4x+3, find the two positive roots.
Polynomial division Watch
- Thread Starter
- 26-01-2016 20:46
- 26-01-2016 21:20
If -1 is a root then a factor would be : (x _ 1) <--- (decide what sign goes in the space). Then, you would long divide using the factor to split the cubic equation into a binomial and a quadratic. Factorise the quadratic and you're done.
- 26-01-2016 21:53
I'm assuming that the equation is equal to 0.
Use the factor theorem, (x-p) = 0 where p is the root.
What I'd do is find the factor and divide it by the whole equation.
It will lead you to a quadratic which you can factorise to find the other two roots .