document.write( "Question 1037823: three numbers form a geometric progression if we double the middle number we get an arithematic progression the common ratio of the geomatric progression is ?
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #652517 by ikleyn(52790)\"\" \"About 
You can put this solution on YOUR website!
.
\n" ); document.write( "three numbers form a geometric progression if we double the middle number we get an arithmetic progression.
\n" ); document.write( "the common ratio of the geometric progression is ?
\n" ); document.write( "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The original geometric progression:  \"a\",  \"ar\",  \"ar%5E2\".\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The new sequence is:  \"a\",  \"2ar\",  \"ar%5E2\".\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The new progression is arithmetic.  It means that  \"a%5B3%5D\" - \"a%5B2%5D\" = \"a%5B2%5D\" - \"a%5B1%5D\".\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "In other words,  \"ar%5E2+-+2ar\" = \"2ar+-+a\".\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Then  \"a%5E2+-+4ar+%2B+a\" = \"0\", ---> \r
\n" ); document.write( "\n" ); document.write( "\"r%5E2+-+4r+%2B+1\" = \"0\",\r
\n" ); document.write( "\n" ); document.write( "\"r%5B1%5D\" = \"1+%2B+sqrt%283%29\"   (positive), \r
\n" ); document.write( "\n" ); document.write( "\"r%5B2%5D\" = \"1+-+sqrt%283%29\"   (negative).\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The previous solution was wrong.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" );