document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=906157>Question 906157</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The effectiveness of a television commercial depends on how many times a viewer watches it. After some experiments an advertising agency found that if the effectiveness E is measured on a scale of 0 to 10, then \r<BR>\n" );
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document.write( "E(n) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%282%2F3%29n+-+160n%5E2+ ALIGN=MIDDLE  ALT=\"+%282%2F3%29n+-+160n%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "A beter view: http://i.imgur.com/kG6LIka.png\r<BR>\n" );
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document.write( "where n is the number of times a viewer watches a given commercial. For a commercial to have maximum effectiveness, how many times should a viewer watch it? ____ times </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #549656 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=549656\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> as I can see on image, you have this\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=E%28n%29+=++%282%2F3%29n+-+%281%2F60%29n%5E2+ ALIGN=MIDDLE  ALT=\"E%28n%29+=++%282%2F3%29n+-+%281%2F60%29n%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "For this problem, E(n) is a function of n. We're trying to find the maximum value of E(n). \r<BR>\n" );
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document.write( " Assuming this is for a pre-calculus or calculus course, they probably want you to take the derivative. \r<BR>\n" );
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document.write( " So the derivative is: <BR>\n" );
document.write( " E'<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28n%29+=+2%2F3+-+%281%2F60%29n ALIGN=MIDDLE  ALT=\"%28n%29+=+2%2F3+-+%281%2F60%29n\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " The maximum then occurs when <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3+-+%281%2F60%29+n+=+0 ALIGN=MIDDLE  ALT=\"2%2F3+-+%281%2F60%29+n+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >. <BR>\n" );
document.write( " So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%281%2F60%29+n+=+2%2F3 ALIGN=MIDDLE  ALT=\"+%281%2F60%29+n+=+2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n+=%282%2F3%29%2F%281%2F60%29=+120%2F3 ALIGN=MIDDLE  ALT=\"n+=%282%2F3%29%2F%281%2F60%29=+120%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n+=+40 ALIGN=MIDDLE  ALT=\"n+=+40\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  </SPAN>\n" );
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