document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1044137>Question 1044137</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use the gauss approach to find a formula for the sum of the even numbers from 2 to 2n  2+4+6+...2n </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #659403 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52780)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=659403\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "It was done in the lesson\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/Sequences-and-series/The-proofs-of-the-formulas-for-arithmetic-progressions.lesson>The proofs of the formulas for arithmetic progressions</A>\r<BR>\n" );
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document.write( "for an arbitrary arithmetic progression.\r<BR>\n" );
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document.write( "See the proof after the formula (3).\r<BR>\n" );
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