document.write( "Question 203195: I need help rationalizing....\r
\n" ); document.write( "\n" ); document.write( "9 times the cubic root 2 over/divided by the cubic root 5 minus cubic root 2.
\n" ); document.write( "Please help! Soory my keyboard will not allow me to type the equation.
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Algebra.Com's Answer #153300 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"%289%2Aroot%283%2C2%29%29%2F%28root%283%2C5%29-root%283%2C2%29%29\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "Let \"x=root%283%2C5%29\" and \"y=root%283%2C2%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%289%2Ay%29%2F%28x-y%29\" Replace each \"root%283%2C5%29\" with \"x\" and each \"root%283%2C2%29\" with \"y\"\r
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\n" ); document.write( "\n" ); document.write( "Now this is where you have to get a bit creative. It's very helpful to remember that \"x%5E3-y%5E3=%28x-y%29%28x%5E2%2Bxy%2By%5E2%29\". Why is this important? Because if you cube a cube root, they will both cancel out (leaving the stuff inside as a remainder).\r
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\n" ); document.write( "\n" ); document.write( "So if we multiply both numerator and denominator by \"x%5E2%2Bxy%2By%5E2\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"%289%2Ay%28x%5E2%2Bxy%2By%5E2%29%29%2F%28%28x-y%29%28x%5E2%2Bxy%2By%5E2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%289%2Ay%28x%5E2%2Bxy%2By%5E2%29%29%2F%28x%5E3-y%5E3%29\" Use the identity given above\r
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\n" ); document.write( "\n" ); document.write( " Plug in \"x=root%283%2C5%29\" and \"y=root%283%2C2%29\"\r
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\n" ); document.write( "\n" ); document.write( " Cube the cube roots (to eliminate them)\r
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\n" ); document.write( "\n" ); document.write( " Subtract\r
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\n" ); document.write( "\n" ); document.write( " Reduce\r
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\n" ); document.write( "\n" ); document.write( " Combine the roots.\r
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\n" ); document.write( "\n" ); document.write( " Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"3%2Aroot%283%2C2%29%28root%283%2C5%5E2%29%2Broot%283%2C10%29%2Broot%283%2C2%5E2%29%29\" Use the identity \"%28root%28n%2Cx%29%29%5Em=root%28n%2Cx%5Em%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%2Aroot%283%2C2%29%28root%283%2C25%29%2Broot%283%2C10%29%2Broot%283%2C4%29%29\" Square 5 to get 25 and square 2 to get 4\r
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\n" ); document.write( "\n" ); document.write( " Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"3%2Aroot%283%2C2%2A25%29%2B3%2Aroot%283%2C2%2A10%29%2B3%2Aroot%283%2C2%2A4%29\" Combine the roots.\r
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\n" ); document.write( "\n" ); document.write( "\"3%2Aroot%283%2C50%29%2B3%2Aroot%283%2C20%29%2B3%2Aroot%283%2C8%29\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So \r
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\n" ); document.write( "\n" ); document.write( "This can be verified (as I have verified it myself) with a calculator.
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