document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=118944>Question 118944</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What function best describes the sequence ( 7,-1,-9,-17,...)? I think it is tn= -8n+1 but I'm not sure . Can someone please explain this to me? Thanks. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #87025 by </B><A HREF=/tutors/aboutme.mpl?userid=mayank><B>mayank(15)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mayank><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=87025\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ans. As the sequence is (7,-1,-9,-17...) the first term clearly is 7.\r<BR>\n" );
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document.write( "Let it be t1.thus t1=7<BR>\n" );
document.write( "if we let second term as t2 then t2=-1 and if we let third term as t3 then t3=-9.<BR>\n" );
document.write( "Let nth term be tn.\r<BR>\n" );
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document.write( "Now considering the sequence as arithmetic sequence, we know that for any arithmetic sequence the nth term is given by tn=t1+(n-1)d, where d is constant difference between consecutive terms.\r<BR>\n" );
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document.write( "Thus here tn=7+(n-1)-8[As difference d here is -8,t2-t1=-1-7=-8]<BR>\n" );
document.write( "thus tn=7-8(n-1)<BR>\n" );
document.write( "thus tn=7-8n+8<BR>\n" );
document.write( "thus tn=15-8n.\r<BR>\n" );
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document.write( "Thus ans is tn=15-8n. Thus this function best describes the above sequence.\r<BR>\n" );
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document.write( "[Note: here we have considered the sequence to be arithmetic one] </SPAN>\n" );
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