Math help

X^3+216=0.... wtf?

How do I factor that again? It's been ages since I've worked with polynomials.

x^3=-216
x=(-216)^(1/3)

That there is a sum of cubes (216 is 6 cubed), so I suspect a teacher that gave that has this in mind:

http://www.csun.edu/~ayk38384/notes/mod8/sumcube.html

Or just do >>2 you fools. x=(-216)^(1/3)=-6, QED.

Yeah but the guy wanted to factor it.

And there are two other solutions in complex number system:
3 + sqroot(27)i and 3 - sqroot(27)i
A cubic can have three unique solutions.  You can find these two others with the quadratic formula applied to the quadratic factor which was found by factoring the cubic as shown in the link above.

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