document.write( "Question 171503: okay so how do i simplify the square root of 128? i know it has something to do with prime numbers i was thinking product rule using 4, 2 and sixteen but i am not sure what to do after that or how to write it! \n" ); document.write( "
Algebra.Com's Answer #126646 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28128%29\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "The goal of simplifying expressions with square roots is to factor the radicand into a product of two numbers. \r
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\n" ); document.write( "\n" ); document.write( "One of these two numbers must be a perfect square. When you take the square root of this perfect square, you will get a rational number.\r
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\n" ); document.write( "\n" ); document.write( "So let's list the factors of 128\r
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\n" ); document.write( "\n" ); document.write( "Factors:\r
\n" ); document.write( "\n" ); document.write( "1, 2, 4, 8, 16, 32, 64, 128\r
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\n" ); document.write( "\n" ); document.write( "Notice how 64 is the largest perfect square, so lets factor 128 into 64*2\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2864%2A2%29\" Factor 128 into 64*2
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\n" ); document.write( "\"sqrt%2864%29%2Asqrt%282%29\" Break up the square roots using the identity \"sqrt%28x%2Ay%29=sqrt%28x%29%2Asqrt%28y%29\"
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\n" ); document.write( "\"8%2Asqrt%282%29\" Take the square root of the perfect square 64 to get 8
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\n" ); document.write( "So the expression \"sqrt%28128%29\" simplifies to \"8%2Asqrt%282%29\"\r
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\n" ); document.write( "Check:\r
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\n" ); document.write( "\n" ); document.write( "Notice if we evaluate the square root of 128 with a calculator we get\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28128%29=11.3137084989848\"\r
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\n" ); document.write( "\n" ); document.write( "and if we evaluate \"8%2Asqrt%282%29\" we get\r
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\n" ); document.write( "\n" ); document.write( "\"8%2Asqrt%282%29=11.3137084989848\"\r
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\n" ); document.write( "\n" ); document.write( "This shows that \"sqrt%28128%29=8%2Asqrt%282%29\". So this verifies our answer
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