document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=211735>Question 211735</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/1592009425/algebrahomeworkh>COLLEGE ALGEBRA</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> pls. help<BR>\n" );
document.write( "10,7,4....to 15th terms<BR>\n" );
document.write( "•Write the next 3 terms,<BR>\n" );
document.write( "•Find the indicated tn,<BR>\n" );
document.write( "•Find the indicated Sn.\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 #159999 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=159999\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 10,7,4,.......<BR>\n" );
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document.write( "This  appears  to  be  an  arithmetic  series  with  rule,,,,-3,,,between  terms<BR>\n" );
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document.write( "The  form  of  the  series  is ,,,a(n) = a(1) + (n-1)d,,,with a(1) =10, d=(-3)<BR>\n" );
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document.write( "check,,1st  term,  a(1) = 10 +(n-1)(-3) = 10,,,ok<BR>\n" );
document.write( ",,,,,,,2nd  term,,, a(2) =10 +(2-1)(-3) = 7,,,,ok<BR>\n" );
document.write( ",,,,,,,3rd  term,,, a(3) =10 +(3-2)(-3) = 4,,,,ok<BR>\n" );
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document.write( ",,,,,,,,,,,,,,,,,,,,a(15) = 10 +(15-1)(-3) = -32,,,,,,answer<BR>\n" );
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document.write( "The  sum of an  arithmetic  series  is the  average * number  of  terms.<BR>\n" );
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document.write( "S = n ( {a(1) +a(n)} /2 )<BR>\n" );
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document.write( "S(15) = (15) * { 10 + (-32) } /2 = (15) * (-11) = - 165<BR>\n" );
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document.write( "check,,,10,7,4,1,-2,-5,-8,-11,-14,-17,-20,-23,-26,-29,-32<BR>\n" );
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document.write( "15 th  term  is indeed  (-32),  and  sum  is (-165),,,ok   </SPAN>\n" );
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