document.write( "Question 991841: 2. Consider the geometric sequence 8, 12, 18, 27, …\r
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Algebra.Com's Answer #611712 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
8, 12, 18, 27\r
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document.write( "We find the common ratio by dividing each term after the\r\n" );
document.write( "first by the preceding term\r\n" );
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document.write( "\"12%2F8=3%2F2\", \"18%2F12=3%2F2\", \"27%2F18=3%2F2\" \r\n" );
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document.write( "So \"r=3%2F2=1.5\"\r\n" );
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document.write( "Use standard formula\r\n" );
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document.write( "\"a%5Bn%5D=a%5B1%5Dr%5E%28n-1%29+\"\r\n" );
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document.write( "\"a%5Bn%5D=8%281.5%29%5E%28n-1%29\"\r\n" );
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document.write( "Substitute 17 for n\r\n" );
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document.write( "\"a%5B17%5D=8%281.5%29%5E%2817-1%29\"\r\n" );
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document.write( "\"a%5B17%5D=5254.727\"\r\n" );
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\n" ); document.write( "(c) Use algebra to find out which is the
\n" ); document.write( " least term of the sequence greater than 1000.
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document.write( "\"a%5Bn%5D=8%281.5%29%5E%28n-1%29%3E1000\"\r\n" );
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document.write( "\"log%28%288%281.5%29%5E%28n-1%29%29%29%3Elog%28%281000%29%29\"\r\n" );
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document.write( "\"log%28%288%29%29%2Blog%28%281.5%29%5E%28n-1%29%29%3E3\"\r\n" );
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document.write( "\"log%28%281.5%29%5E%28n-1%29%29%3E3-log%28%288%29%29\"\r\n" );
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document.write( "\"%28n-1%29log%28%281.5%29%29%3E3-log%28%288%29%29\"\r\n" );
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document.write( "\"n-1%3E%283-log%28%288%29%29%29%2Flog%28%281.5%29%29\"\r\n" );
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document.write( "\"n%3E%283-log%28%288%29%29%29%2F%28log%28%281.5%29%29%29%2B1\"\r\n" );
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document.write( "\"n=12.90808689\"\r\n" );
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document.write( "So the next integer is 13\r\n" );
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document.write( "You can substitute and find that the 13th term is 1037.971\r\n" );
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document.write( "And that is the least term of the sequence greater than 1000\r\n" );
document.write( "because the 12th term is only 691.980\r\n" );
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document.write( "Edwin

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