Question is find all the roots :
z^4 + 2z^3 + 5z^2 + 8z + 4 = 0
I"m stuck at the beginning of this question. But i knew how to do this type of question and only does not know how to start.
Thanks.
1. By trial and error you can see that z = -1 is a root of the equation. (Actually z = -1 is a double root of the equation) Use long division to get the remaining terms.