Hi Kevin,
Do you have an example of the working on how you get the factors of a cubic equations that have complex parts?
Answer:
Find the first root by trial and error
![[x=-2]](http://itsligo.learnonline.ie/filter/tex/pix.php/a2bf2d0183b849acaa5c0e278a1bc3ee.gif "[x=-2]")
This is true so 
is a root and 
is a factor
Dividing 
by gives
Now use the formula
to get
the remaining two roots
With a simple school mathematics -2 is not a root of $$x^3 - x + 10$$ because $$(-2)^3 - (-2) + 10 = -8 + 2 + 10 = 4 \not = 0 $$ ... and the only real root is somewhere near -2.31 
What's the main problem? Big letters in $$X^3$$ or the method of getting factors of a cubic equations that have complex parts?
( ... a correct numeric solution can be found for example with http://www.akiti.ca/Quad3Deg.html : real root is about
-2.3089073197650927
and complex roots
1.1544536598825463 + 1.731557032975991 $$i$$ and
1.1544536598825463 - 1.731557032975991 $$i$$ ... )