posted by anon on .
solve the following equation in the real number system
3x^3 - 20x^2 + 29x +12 = 0
Ok I thought I knew how to do this but I guess I don't. Help me! Please!
A general cubic is hard to solve. So, expect an easy root first. Any rational root of the form a/b will be such that a divides 12 and b divides 3
A little synthetic division will show that
3x^3 - 20x^2 + 29x +12
= (x-3)(3x^2 - 11x - 4)
SO, knowing the factors, you should have no trouble finding the roots . . .
Thank you that helps a lot!