document.write( "Question 969177: Given the sequence in the table below, determine the sigma notation of the sum for term 4 through term 15.\r
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Algebra.Com's Answer #592114 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "That's a geometric sequence.\r\n" );
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document.write( "\"a%5Bn%5D+=+a%5B1%5Dr%5E%28n-1%29\" where \"a%5B1%5D=4\" and \"r=-3\"\r\n" );
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document.write( "So the nth term is\r\n" );
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document.write( "\"a%5Bn%5D+=+4%2A%28-3%29%5E%28n-1%29\"\r\n" );
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document.write( "\"sum%28%284%2A%28-3%29%5E%28n-1%29%29%2Cn=4%2C15%29\"\r\n" );
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document.write( "Edwin
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