document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1151137>Question 1151137</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write each series as a summation in sigma notation.<BR>\n" );
document.write( "10+20+40+80 </SPAN>\n" );
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document.write( "Answer: <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \displaystyle {\color{red}{\sum_{k=1}^{4}10(2)^{k-1}}}\">\r<BR>\n" );
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document.write( "More explanation:\r<BR>\n" );
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document.write( "If you plugged in k = 1, you'd get <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large 10(2)^{k-1} = 10(2)^{1-1} = 10\"> as the first term.<BR>\n" );
document.write( "If you plugged in k = 2, you'd get <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large 10(2)^{k-1} = 10(2)^{2-1} = 20\"> as the second term.<BR>\n" );
document.write( "If you plugged in k = 3, you'd get <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large 10(2)^{k-1} = 10(2)^{3-1} = 40\"> as the third term.<BR>\n" );
document.write( "If you plugged in k = 4, you'd get <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large 10(2)^{k-1} = 10(2)^{4-1} = 80\"> as the fourth term.\r<BR>\n" );
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document.write( "So,  <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large \displaystyle \sum_{k=1}^{4}10(2)^{k-1} = 10 + 20 + 40 + 80\">\r<BR>\n" );
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document.write( "The sequence 10, 20, 40, 80, ... is geometric with <BR>\n" );
document.write( "a = first term = 10<BR>\n" );
document.write( "r = common ratio = 2<BR>\n" );
document.write( "The general nth term of a geometric sequence is <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large a(r)^{n-1}\"><BR>\n" );
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