document.write( "Question 1205019: Find the common ratio, given that it is negative, of a GP whose first term is 8 and whose 5th term is ½. \n" ); document.write( "
Algebra.Com's Answer #841595 by ikleyn(52794)\"\" \"About 
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\n" ); document.write( "Find the common ratio, given that it is negative, of a GP whose first term is 8 and whose 5th term is ½.
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document.write( "Let \"r\" be the common ratio, which is an unknown value in this problem.\r\n" );
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document.write( "First term of the GP is 8; 5th term is  \"8%2Ar%5E%285-1%29\" = \"8%2Ar%5E4\", according to the formula\r\n" );
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document.write( "So, \"8%2Ar%5E4\" = \"1%2F2\".\r\n" );
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document.write( "Divide both sides bt 8:  \"r%5E4\" = \"1%2F16\".\r\n" );
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document.write( "Take the root of degree 4 of both sides.  In real numbers, you will get\r\n" );
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document.write( "    r = +/- \"1%2F2\".\r\n" );
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document.write( "We are given that common ratio value is negative, so from two values \"1%2F2\" and \"-1%2F2\"\r\n" );
document.write( "we select the ANSWER  r = \"-1%2F2\".\r\n" );
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\n" ); document.write( "\n" ); document.write( "For introductory lessons on arithmetic progressions see \r
\n" ); document.write( "\n" ); document.write( "    - Arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - The proofs of the formulas for arithmetic progressions \r
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\n" ); document.write( "\n" ); document.write( "    - Word problems on arithmetic progressions\r
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