document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=195831>Question 195831</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find the number of terms of a geometric sequence with, first term 1/64, common ratio 2 and the last term 512<BR>\n" );
document.write( "please i need help please help..... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #146856 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=146856\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> std  form  is  a(n) = a(1) r^(n-1)<BR>\n" );
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document.write( "a(1)=1/64,,,,given<BR>\n" );
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document.write( "r = 2,,,,given<BR>\n" );
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document.write( "a(n) = 512,,,,given<BR>\n" );
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document.write( "substituting<BR>\n" );
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document.write( "512 = (1/64) * 2^  (n-1)<BR>\n" );
document.write( "32768 = 2^(n-1)<BR>\n" );
document.write( "log  both  sides<BR>\n" );
document.write( "log 32768 = log 2^(n-1) = (n-1) log2<BR>\n" );
document.write( "log 32768 / log 2 = n-1<BR>\n" );
document.write( "15 = n-1<BR>\n" );
document.write( "n=16,,,,  ANSWER<BR>\n" );
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document.write( "check<BR>\n" );
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document.write( "a(16) = (1/64) *2^ (16-1) =(1/64) * 2^15 = 512  ok </SPAN>\n" );
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