How do you find all the roots (four) to this equation knowing that one of them is 1+3i?
x^4+3x^3+6x^2+2x-60 How do you find all the roots (four) to this equation knowing that one of them is 1+3i?
x^4+3x^3+6x^2+2x-60 @Mathematics

Question

anonymous · Answer

1-3i is another.  divide them out (after multiplying together) using polynomial long division or synthetic division and then factor.  Alternately, graph the function and find the other two that way.

anonymous · Answer

Okay, what do you mean divide them out after multiplying them together?

turingtest · Answer

(1-3i)(1+3i)=1-3=-2
so x+2 is a factor
can you do the synthetic division?

anonymous · Answer

yes, i did the synthetic division for -2 and the bottom level ended up being 1 -5 16 -30 0

anonymous · Answer

where do I go from there to find the last root?