document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1092090>Question 1092090</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write the sum using summation notation, assuming the suggested pattern continues.\r<BR>\n" );
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document.write( "-9 - 3 + 3 + 9 + ... + 81\r<BR>\n" );
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document.write( "Can you please explain so I get it, because i know how to write this in the simple way, i just get really confused when it comes to using sigma and everything..  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #706592 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=706592\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Start with the starting value, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-9 ALIGN=MIDDLE  ALT=\"-9\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "Then to get each successive term find the amount added, <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3-%28-9%29=-3%2B9=6 ALIGN=MIDDLE  ALT=\"-3-%28-9%29=-3%2B9=6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So add 6 to each previous value to get the next.<BR>\n" );
document.write( "Let's choose k as the index.<BR>\n" );
document.write( "So,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-9%2B6%2A%28k-1%29 ALIGN=MIDDLE  ALT=\"-9%2B6%2A%28k-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the formula to get any value.<BR>\n" );
document.write( "So for the first value, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=1 ALIGN=MIDDLE  ALT=\"k=1\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-9%2B6%2A%281-1%29=-9 ALIGN=MIDDLE  ALT=\"-9%2B6%2A%281-1%29=-9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Second, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=2 ALIGN=MIDDLE  ALT=\"k=2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-9%2B6%2A%282-1%29=-9%2B6=-3 ALIGN=MIDDLE  ALT=\"-9%2B6%2A%282-1%29=-9%2B6=-3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "And so on.<BR>\n" );
document.write( "So then stick this into the summation notation.<BR>\n" );
document.write( "You can simplify too,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-9%2B6%28k-1%29=-9%2B6k-6=6k-15 ALIGN=MIDDLE  ALT=\"-9%2B6%28k-1%29=-9%2B6k-6=6k-15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5Bn%5D=sum%28%286k-15%29%2Ck=1%2Cn%29 ALIGN=MIDDLE  ALT=\"S%5Bn%5D=sum%28%286k-15%29%2Ck=1%2Cn%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  </SPAN>\n" );
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