document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1017219>Question 1017219</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the next two terms in the sequence –5, 8, –13, 20, –29, …. Write a formula for the nth term. Identify the formula as explicit or recursive </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #633570 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=633570\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i believe the formula will be:\r<BR>\n" );
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document.write( "An = -1 * An-1 + (-1)^n * (2n-1)\r<BR>\n" );
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document.write( "it's a recursive formula that depends on the value of the term in the sequence immediately before it.\r<BR>\n" );
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document.write( "set A1 = -5\r<BR>\n" );
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document.write( "when n = 1, A1 = -5\r<BR>\n" );
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document.write( "when n = 2, An = -1 * An-1 + (-1)^n * (2n-1) becomes:<BR>\n" );
document.write( "-1 * -5 + (-1)^2 * (2*2-1) which becomes:<BR>\n" );
document.write( "-5 + 1 * (4 - 1) which becomes:<BR>\n" );
document.write( "5 + 1 * 3) which becomes:<BR>\n" );
document.write( "5 + 3 which is equal to 8.\r<BR>\n" );
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document.write( "when n = 3, An = -1 * An-1 + (-1)^n * (2n-1) becomes:<BR>\n" );
document.write( "-1 * 8 + (-)^3 * (2*3-1) which becomes:<BR>\n" );
document.write( "-8 - 1 * (6 - 1) which becomes:<BR>\n" );
document.write( "-8 - 1 * 5 which becomes:<BR>\n" );
document.write( "-8 - 5 which is equal to -13.\r<BR>\n" );
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document.write( "when n = 4, An = -1 * An-1 + (-1)^n * (2n-1) becomes:<BR>\n" );
document.write( "-1 * -13 + (-1)^4 * (2*4-1) which becomes:<BR>\n" );
document.write( "13 + 1 * (8-1) which becomes:<BR>\n" );
document.write( "13 + 1 * 7 which becomes:<BR>\n" );
document.write( "13 + 7 = 20\r<BR>\n" );
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document.write( "when n = 5, An = -1 * An-1 + (-1)^n * (2n-1) becomes:<BR>\n" );
document.write( "-1 * 20 + (-1)^5 * (2*5-1) which becomes:<BR>\n" );
document.write( "-20 - 1 * (10-1) which becomes:<BR>\n" );
document.write( "-20 - 1 * 9 which becomes:<BR>\n" );
document.write( "-20 - 9 = -29\r<BR>\n" );
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document.write( "the formula looks good.\r<BR>\n" );
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document.write( "your solution is that the formula is:\r<BR>\n" );
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document.write( "An = -1 * An-1 + (-1)^n * (2n-1)\r<BR>\n" );
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document.write( "An is the value of the nth term in the sequence starting at n = 2.<BR>\n" );
document.write( "An-1 is the value of the term immediately preceding the nth term.<BR>\n" );
document.write( "n is the number of the term with the first term in the sequence starting at 1.<BR>\n" );
document.write( "the value of A1 is set to -5.\r<BR>\n" );
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document.write( " \r<BR>\n" );
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document.write( " </SPAN>\n" );
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