document.write( "Question 1189826: The first term of a G.P is x and 3rd term is y. Find an expression
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Algebra.Com's Answer #821311 by ikleyn(52797) $\"\"$ $\"About$

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\n" ); document.write( "(a) the first term of a G.P is x and 3rd term is y. find an expression for the common ratio in terms of x and y. \r
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document.write( "     = x;    = y = .\r\n" );
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document.write( "    So,  y = x*r^2,  which gives  for the common ratio  r = +/- .      ANSWER\r\n" );
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document.write( "    Notice that this formula for the common ratio \"r\" works in real numbers  IF and only IF  \r\n" );
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document.write( "    the ratio   is non-negative, which means that both x and y must be of the same sign, and both are not zero.\r\n" );
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document.write( "     = 8;    = 18 =  = .\r\n" );
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document.write( "    It gives  r =  =  = +/- .      \r\n" );
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document.write( "    Since the condition says that common ratio is positive, \r\n" );
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document.write( "    it leaves only one option for the common ratio  r =  = 1.5.   ANSWER\r\n" );
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