SOLUTION: If x=3^1/3+3^-1/3 Then 3x^3-9x equal to ?

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Question 1005104: If x=3^1/3+3^-1/3
Then 3x^3-9x equal to ?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If x=3^1/3+3^-1/3
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x = 3^(1/3) + 1/3^(1/3)
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x = [3^(2/3) +1]/(3^(1/3))
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x = 2.1356
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Then 3x^3-9x equal to ?
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= 3(2.1356)^3-9(2.1356)
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= 10
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Cheers,
Stan H.
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