document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1119500>Question 1119500</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How to write a formula for the nth term of each geometric sequence below? Then use the formula to find a8, the eight term of the sequence.<BR>\n" );
document.write( "(a) 4, -4, 4, -4,.....<BR>\n" );
document.write( "(b) 16, 8, 4,..... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #735076 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=735076\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The general form for the nth term of a geometric sequence is a_n = ar^(n-1)<BR>\n" );
document.write( "where a = the 1st term and r is the common ratio\r<BR>\n" );
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document.write( "(a) In this case, r =-4/4 = -1, and a = 4<BR>\n" );
document.write( "Thus a_n = 4(-1)^(n-1)\r<BR>\n" );
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document.write( "(b) In this case, r = 8/16 = 1/2, a = 16<BR>\n" );
document.write( "Thus a_n = 16(1/2)^(n-1)<BR>\n" );
document.write( " </SPAN>\n" );
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