document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=927581>Question 927581</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the sum of the series  5 + 20 + 80 + ....+ 20 480\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #563157 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=563157\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5+%2B+20+%2B+80+ ALIGN=MIDDLE  ALT=\"5+%2B+20+%2B+80+\"   DISABLED_style= \"max-width:90%; height:auto;\" >+ ....+ <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20480 ALIGN=MIDDLE  ALT=\"20480\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B1%5D=5 ALIGN=MIDDLE  ALT=\"a%5B1%5D=5\"   DISABLED_style= \"max-width:90%; height:auto;\" >...first term<BR>\n" );
document.write( "if you multiply it by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4 ALIGN=MIDDLE  ALT=\"4\"   DISABLED_style= \"max-width:90%; height:auto;\" > you got second term <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20 ALIGN=MIDDLE  ALT=\"20\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then if you multiply it by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4 ALIGN=MIDDLE  ALT=\"4\"   DISABLED_style= \"max-width:90%; height:auto;\" > you got third term <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=80 ALIGN=MIDDLE  ALT=\"80\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "if we write <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4 ALIGN=MIDDLE  ALT=\"4\"   DISABLED_style= \"max-width:90%; height:auto;\" > as <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%5E2 ALIGN=MIDDLE  ALT=\"2%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >, but to get first term we can write <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%5E%282n-2%29 ALIGN=MIDDLE  ALT=\"2%5E%282n-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so, general formula is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5Bn%5D=5%2A2%5E%282n-2%29 ALIGN=MIDDLE  ALT=\"a%5Bn%5D=5%2A2%5E%282n-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "now find which term is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20480 ALIGN=MIDDLE  ALT=\"20480\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20480=5%2A2%5E%282n-2%29 ALIGN=MIDDLE  ALT=\"20480=5%2A2%5E%282n-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20480%2F5=2%5E%282n-2%29 ALIGN=MIDDLE  ALT=\"20480%2F5=2%5E%282n-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4096=2%5E%282n-2%29 ALIGN=MIDDLE  ALT=\"4096=2%5E%282n-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2=2%5E%282n-2%29 ALIGN=MIDDLE  ALT=\"2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2%2A2=2%5E%282n-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%5E12=2%5E%282n-2%29 ALIGN=MIDDLE  ALT=\"2%5E12=2%5E%282n-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >...if bases same, then\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12=2n-2 ALIGN=MIDDLE  ALT=\"12=2n-2\"   DISABLED_style= \"max-width:90%; height:auto;\" > ...solve for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n ALIGN=MIDDLE  ALT=\"n\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2B2=2n ALIGN=MIDDLE  ALT=\"12%2B2=2n\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=14=2n ALIGN=MIDDLE  ALT=\"14=2n\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7=n ALIGN=MIDDLE  ALT=\"7=n\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "also find:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B4%5D=5%2A2%5E%282%2A4-2%29 ALIGN=MIDDLE  ALT=\"a%5B4%5D=5%2A2%5E%282%2A4-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B4%5D=5%2A2%5E%286%29=320 ALIGN=MIDDLE  ALT=\"a%5B4%5D=5%2A2%5E%286%29=320\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B5%5D=5%2A2%5E%282%2A5-2%29=5%2A2%5E%288%29=1280 ALIGN=MIDDLE  ALT=\"a%5B5%5D=5%2A2%5E%282%2A5-2%29=5%2A2%5E%288%29=1280\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B6%5D=5%2A2%5E%282%2A6-2%29=5%2A2%5E%2810%29=5120 ALIGN=MIDDLE  ALT=\"a%5B6%5D=5%2A2%5E%282%2A6-2%29=5%2A2%5E%2810%29=5120\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "then the sum is:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sum%285%2A2%5E%282n-2%29%2Cn=1%2C7%29=5%2B20%2B80%2B320%2B1280%2B5120%2B20480+=27305 ALIGN=MIDDLE  ALT=\"sum%285%2A2%5E%282n-2%29%2Cn=1%2C7%29=5%2B20%2B80%2B320%2B1280%2B5120%2B20480+=27305\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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