document.write( "Question 1185339: The first term of an infinite geometric sequence is 4. The sum of the infinite
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Algebra.Com's Answer #816163 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
A) Find the sum of the first 8 terms
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document.write( "\"S%5Binfinity%5D\"\"%22%22=%22%22\"\"a%5B1%5D%2F%281-r%5E%22%22%29\"\r\n" );
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document.write( "\"200\"\"%22%22=%22%22\"\"4%5E%22%22%2F%281-r%5E%22%22%29\"\r\n" );
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document.write( "\"200%281-r%29\"\"%22%22=%22%22\"\"4\"\r\n" );
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document.write( "Divide both sides by 4\r\n" );
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document.write( "\"50%281-r%29\"\"%22%22=%22%22\"\"1\"\r\n" );
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document.write( "\"50-50r\"\"%22%22=%22%22\"\"1\"\r\n" );
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document.write( "\"-50r\"\"%22%22=%22%22\"\"-49\"\r\n" );
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document.write( "\"r\"\"%22%22=%22%22\"\"49%2F50\"\r\n" );
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document.write( "\"r\"\"%22%22=%22%22\"\"0.98\"\r\n" );
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document.write( "\"S%5Bn%5D\"\"%22%22=%22%22\"\"a%5B1%5D%281-r%5En%29%2F%281-r%5E%22%22%29\"\r\n" );
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document.write( "\"S%5B8%5D\"\"%22%22=%22%22\"\"4%281-0.98%5E8%29%2F%281-0.98%5E%22%22%29\"\r\n" );
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document.write( "\"S%5B8%5D\"\"%22%22=%22%22\"\"29.84739548\"
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document.write( "\"S%5Bn%5D\"\"%22%22=%22%22\"\"4%281-0.98%5En%29%2F%281-0.98%5E%22%22%29\"\"%22%22%3E%22%22\"\"163\"\r\n" );
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document.write( "\"%284%2F.02%29%281-0.98%5En%29\"\"%22%22%3E%22%22\"\"163\"\r\n" );
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document.write( "\"200%281-0.98%5En%29\"\"%22%22%3E%22%22\"\"163\"\r\n" );
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document.write( "\"1-0.98%5En\"\"%22%22%3E%22%22\"\"163%2F200\"\r\n" );
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document.write( "\"1-0.98%5En\"\"%22%22%3E%22%22\"\"0.815\"\r\n" );
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document.write( "\"-0.98%5En\"\"%22%22%3E%22%22\"\"-0.185\"\r\n" );
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document.write( "\"0.98%5En\"\"%22%22%3E%22%22\"\"0.185\"\r\n" );
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document.write( "Take natural logs of both side:\r\n" );
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document.write( "\"ln%280.98%5En%29\"\"%22%22%3E%22%22\"\"ln%280.185%29\"\r\n" );
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document.write( "\"n%2Aln%280.98%29\"\"%22%22%3E%22%22\"\"ln%280.185%29\"\r\n" );
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document.write( "\"n\"\"%22%22%3E%22%22\"\"ln%280.185%29%2Fln%280.98%29\"\r\n" );
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document.write( "\"n\"\"%22%22%3E%22%22\"\"83.52343215\"\r\n" );
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document.write( "The least integer than n can take on greater \r\n" );
document.write( "than that is 84.\r\n" );
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document.write( "Edwin
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