document.write( "Question 878997: The least value of n for which sum of n terms of series 1+3+9(3square)+.....is greater than 7000 is
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Algebra.Com's Answer #530480 by AnlytcPhil(1807) $\"\"$ $\"About$

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document.write( "It's a geometric series with a₁ = 1 and r = 3.\r\n" );
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document.write( "The sum of a geometric series is given by the formula:\r\n" );
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document.write( "We set that greater than 7000\r\n" );
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document.write( "Multiply both sides by 2 to clear the fraction:\r\n" );
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document.write( "Add 1 to both sides\r\n" );
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document.write( "Take the ln or log of both sides:\r\n" );
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document.write( "Use the property of logs that says that the log of \r\n" );
document.write( "an exponential is the product of the exponent and \r\n" );
document.write( "the log of the base.\r\n" );
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document.write( "Divide both sides by log(3)\r\n" );
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document.write( "The least value of n greater than that is when n=9.\r\n" );
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document.write( "Edwin

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