document.write( "Question 154073: I was trying to solve this problem, I tried rationalizing the denominator but I could not eliminate the middle terms in the denominator because the exponents of the variable inside the cube root sign is not the same. I took this problem from the College Algebra book by William Hart, 4th Edition. This is under exercise 53, problem number 148, page 127. This is the problem:
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\n" ); document.write( "If only the index of the radicals in the denominator is equal to 2,and not a 3 (which is a cube root) I could immediately perform rationalization.\r
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\n" ); document.write( "\n" ); document.write( "jomar \r
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Algebra.Com's Answer #113600 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "To rationalize the denominator when the denominator is the \r\n" );
document.write( "difference of cube roots, you must use the factorization of \r\n" );
document.write( "the difference of cubes formula.\r\n" );
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document.write( "But write the left side on the right and vice-versa, so you\r\n" );
document.write( "can better see what to do:\r\n" );
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document.write( "Let A and B be the terms of the denominator:\r\n" );
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document.write( "Substituting into ,\r\n" );
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document.write( "Simplifying,\r\n" );
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document.write( "So as you can see from that, to rationalize the denominator,\r\n" );
document.write( "you must multiply top and bottom by \r\n" );
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document.write( "which can be simplified a little:\r\n" );
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document.write( "We have just finished multiplying the bottom by that \r\n" );
document.write( "and gotten the rational expression .\r\n" );
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document.write( "Now we must multiply the numerator, which is\r\n" );
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document.write( "by it too:\r\n" );
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document.write( "Combine like terms:\r\n" );
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document.write( "Now put this over the denominator which we rationalized\r\n" );
document.write( "first:\r\n" );
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document.write( "Edwin

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