SOLUTION: hey can yousolve x^3+216=0

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Question 714050: hey can yousolve x^3+216=0
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
x^3+216=0
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x^3 = -216
x^3 = 216cis(180)
x = 6cis(60) = 6(cos(60) = i*sin(60))
x = 6cis(180) = -6
x = 6cis(300)
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I don't know if you want all 3
x = -6 is the most obvious, and the only real solution