SOLUTION: Rational exponents x^2/3-2x^1/3-8=0 Solve the equation

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Question 354693: Rational exponents
x^2/3-2x^1/3-8=0
Solve the equation

Found 2 solutions by stanbon, vleith:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Rational exponents
x^(2/3)-2x^(1/3)-8=0
Solve the equation
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Quadratic equation with variable x^(1/3).
Factor:
(x^(1/3)-4)(x^(1/3)+2) = 0
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x^(1/3) = 4 or x^(1/3) = -2
x = (4)^3 or x = (-2)^3
x = 84 or x = -8
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Cheers,
Stan H.

Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E%282%2F3%29-2x%5E%281%2F3%29-8=0
%28x%5E%281%2F3%29+-+4%29%28x%5E%281%2F3%29+%2B+2%29+=+0
so either %28x%5E%281%2F3%29+-+4%29+=+0 or %28x%5E%281%2F3%29+%2B+2%29=0
Solve for that
%28x%5E%281%2F3%29+-+4%29+=+0
x%5E%281%2F3%29+=+4
x+=+4%5E3+=+64
or
%28x%5E%281%2F3%29+%2B+2%29=0
x%5E%281%2F3%29+=+-2
x+=+-8