document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1046326>Question 1046326</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find the sum of the G.P 1 + 3 + 9 + 27 + ------- + 729? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #661791 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=661791\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> sum is the sum of a1(1-r^(n+1))/(1-r)<BR>\n" );
document.write( "3 is the common ratio, the first term is 1<BR>\n" );
document.write( "The last term is 3^6, the first term is 3^0, so we use 3^(n+1) in the formula<BR>\n" );
document.write( "1(1-3^7)/(-2)<BR>\n" );
document.write( "-2186*(-1/2)=1093<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "1+3+9+27+81+243+729=1093 </SPAN>\n" );
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