document.write( "Question 761611: the sum to infinity of a geometric progression is twice the sum of the first two terms. find possible values of the common ratio. \n" ); document.write( "
Algebra.Com's Answer #463331 by ramkikk66(644)\"\" \"About 
You can put this solution on YOUR website!
Similar to problem 463319.\r
\n" ); document.write( "\n" ); document.write( "If 'a' is the first term, and 'r' the common ratio of the GP,
\n" ); document.write( "the sum to infinity is given by the formula \"S+=+a+%2F+%281+-+r%29\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"2%28a+%2B+a%2Ar%29+=+a+%2F+%281-r%29\"\r
\n" ); document.write( "\n" ); document.write( "Cancelling out a from both sides\r
\n" ); document.write( "\n" ); document.write( "\"2+%2B+2%2Ar+=+1%2F%281-r%29\"\r
\n" ); document.write( "\n" ); document.write( "\"2+-+2%2Ar%5E2+=+1\"\r
\n" ); document.write( "\n" ); document.write( "Simplifying:\r
\n" ); document.write( "\n" ); document.write( "\"r%5E2+=+1%2F2\" \r
\n" ); document.write( "\n" ); document.write( "\"r+=+1%2Fsqrt%282%29\" or \"r+=+-1%2Fsqrt%282%29\"\r
\n" ); document.write( "\n" ); document.write( ":)
\n" ); document.write( "
\n" ); document.write( "
\n" );