document.write( "Question 277573: I am having some difficulties working functions which have numbers raised to fractional powers, like the following question.\r
\n" ); document.write( "\n" ); document.write( "Solve: x^(2/3) - 2x^(1/3) - 15 = 0\r
\n" ); document.write( "\n" ); document.write( "I understand using a placeholder thing, reorganizing the problem, and then solving for the placeholder, but I am having problems with raising to the fractional powers while solving for X. Could you explain how please?\r
\n" ); document.write( "\n" ); document.write( "I got this question solved down to \"+u%5E2+-+2u+-15+=+0+\" where u = x^(1/3) The possible solutions for u are 5, and -3. I need help solving for X now.\r
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Algebra.Com's Answer #202086 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Since \"u=x%5E%281%2F3%29%5E%22%22\", we can convert to radical notation to get \"u=root%283%2Cx%29\". It's just a different way to same thing.\r
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\n" ); document.write( "\n" ); document.write( "Now because the possible solutions for 'u' (no pun intended) are 5 and -3, this means that \"u=5\" or \"u=-3\"\r
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\n" ); document.write( "\n" ); document.write( "Let's find the solution(s) in terms of 'x' when \"u=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"u=root%283%2Cx%29\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"5=root%283%2Cx%29\" Plug in \"u=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"%285%29%5E3=%28root%283%2Cx%29%29%5E3\" Cube both sides to undo the cube root.\r
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\n" ); document.write( "\n" ); document.write( "\"%285%29%5E3=x\" Cube the cube root of 'x' to just get 'x'.\r
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\n" ); document.write( "\n" ); document.write( "\"125=x\" Cube 5 to get 125.\r
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\n" ); document.write( "\n" ); document.write( "So one solution in terms of 'x' is \"x=125\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's find the solution(s) in terms of 'x' when \"u=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"u=root%283%2Cx%29\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-3=root%283%2Cx%29\" Plug in \"u=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-3%29%5E3=%28root%283%2Cx%29%29%5E3\" Cube both sides to undo the cube root.\r
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\n" ); document.write( "\n" ); document.write( "\"%28-3%29%5E3=x\" Cube the cube root of 'x' to just get 'x'.\r
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\n" ); document.write( "\n" ); document.write( "\"-27=x\" Cube -3 to get -27.\r
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\n" ); document.write( "\n" ); document.write( "So another solution in terms of 'x' is \"x=-27\"\r
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\n" ); document.write( "\n" ); document.write( "So the solutions in terms of 'x' are \"x=125\" or \"x=-27\"
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