SOLUTION: fractional exponents inq: {{{ 2x^(2/3) + x^(1/3) - 15 = 0}}} solve for x. this question is not from the book. its from a worksheet my teacher created.
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Question 142397: fractional exponents inq: solve for x. this question is not from the book. its from a worksheet my teacher created. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! fractional exponents inq: solve for x.
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Let x^(1/3) = w
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Rewrite the equation substituting w for x^(1/3)
2w^2 + w - 15 = 0
2w^2 + 6w - 5w - 15 = 0
2w(w+3)-5(w+3) = 0
(w+3)(2w-5) = 0
w = -3 or w = 5/2
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Substitute back to solve for "x":
x^(1/3) = -3 or x^(1/3) = (5/2)
x = -27 or x = 125/8
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Cheers,
Stan H.
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