document.write( "Question 1017122: the answer of a sum is given. write the sum that was asked in sigma notation
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Algebra.Com's Answer #634598 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
\"8191.5\"\"%22%22=%22%22\"\"%28expr%283%2F2%29%284%5En-1%29%29%2F3\"
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document.write( "Write the denominator 3 as 4-1\r\n" );
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document.write( "\"8191.5\"\"%22%22=%22%22\"\"expr%283%2F2%29%284%5En-1%29%2F%284-1%29%29\"\r\n" );
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document.write( "Compare to the sum formula for a geometric series:\r\n" );
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document.write( "\"S%5Bn%5D\"\"%22%22=%22%22\"\"a%5B1%5D%28r%5En-1%29%2F%28r-1%29%29\"\"%22%22=%22%22\"\"sum%28a%5B1%5D%2Ar%5Ek%2Ck=1%2Cn%29\" \r\n" );
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document.write( "\"a%5B1%5D\"\"%22%22=%22%22\"\"3%2F2\", \"r\"\"%22%22=%22%22\"\"4\"\r\n" );
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document.write( "Also solve for n\r\n" );
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document.write( "\"8191.5\"\"%22%22=%22%22\"\"expr%283%2F2%29%284%5En-1%29%2F3%29\"\r\n" );
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document.write( "Multiply both sides by 3\r\n" );
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document.write( "\"8191%2A3\"\"%22%22=%22%22\"\"expr%283%2F2%29%284%5En-1%29\"\r\n" );
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document.write( "Multiply both sides by 2\r\n" );
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document.write( "\"8191.5%2A3%2A2\"\"%22%22=%22%22\"\"expr%283%29%284%5En-1%29\"\r\n" );
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document.write( "Divide both sides by 3\r\n" );
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document.write( "\"8191.5%2A2\"\"%22%22=%22%22\"\"4%5En-1\"\r\n" );
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document.write( "\"16383\"\"%22%22=%22%22\"\"4%5En-1\"\r\n" );
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document.write( "\"16384\"\"%22%22=%22%22\"\"4%5En\"\r\n" );
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document.write( "\"4%5E7\"\"%22%22=%22%22\"\"4%5En\"\r\n" );
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document.write( "\"7\"\"%22%22=%22%22\"\"n\"\r\n" );
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document.write( "Substitute in \r\n" );
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document.write( "\"sum%28a%5B1%5D%2Ar%5Ek%2Ck=1%2Cn%29\"\r\n" );
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document.write( "\"sum%28%28expr%283%2F2%29%2A4%5Ek%29%2Ck=1%2Cn%29\"\r\n" );
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document.write( "Edwin
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