document.write( "Question 109091: Given h(x), find a pair of functions f and g such that h(x) = fgg(x):\r
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Algebra.Com's Answer #79556 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Given h(x), find a pair of functions f and g such that h(x) = fgg(x):\r\n" );
document.write( "h(x) = square root \"sqrt%28+%287x%5E7%2B1%29%2F%287x%5E7-1%29+%29++\". \r\n" );
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document.write( "Pick g(x) as any expression in x from the whole expression\r\n" );
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document.write( "\"sqrt%28+%287x%5E7%2B1%29%2F%287x%5E7-1%29+%29++\"\r\n" );
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document.write( "such that if you were to substitute u for that expression,\r\n" );
document.write( "there will be no x's left.\r\n" );
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document.write( "Suppose we pick u to be \"7x%5E7\", then we replace both\r\n" );
document.write( "the \"7x%5E7\"'s by u and get\r\n" );
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document.write( "\"sqrt%28+%28u%2B1%29%2F%28u-1%29+%29++\"  \r\n" );
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document.write( "g(x) is simply equal to what we picked u to be, that is,\r\n" );
document.write( "g(x) = \"7x%5E7\" \r\n" );
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document.write( "To get f(x) we substitute x for u in\r\n" );
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document.write( "\"sqrt%28+%28u%2B1%29%2F%28u-1%29+%29++\" \r\n" );
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document.write( "and get \r\n" );
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document.write( "\"sqrt%28+%28x%2B1%29%2F%28x-1%29+%29++\"\r\n" );
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document.write( "So  \r\n" );
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document.write( "f(x) =  \"sqrt%28+%28x%2B1%29%2F%28x-1%29+%29++\"\r\n" );
document.write( "g(x) =  \"7x%5E7\"\r\n" );
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document.write( "Checking:\r\n" );
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document.write( "h(x) = fgg(x) = f(g(x)) = f(\"7x%5E7\") =  \"sqrt%28+%287x%5E7%2B1%29%2F%287x%5E7-1%29+%29++\".\r\n" );
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document.write( "Edwin
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