document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1098756>Question 1098756</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A particle moves along a line so that its position at any time t>=0 is given by s(t) = 2+7t-t^2\r<BR>\n" );
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document.write( "At which of the following times is the particle moving to the left?<BR>\n" );
document.write( "A. t=0 B. t=1 C. t=2 D. t=7/2 E. t= 4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #713160 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=713160\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A particle moves along a line so that its position at any time t>=0 is given by s(t) = 2+7t-t^2\r<BR>\n" );
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document.write( "At which of the following times is the particle moving to the left?<BR>\n" );
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document.write( "Speed = 1st derivative of position.<BR>\n" );
document.write( "s(t) = 2+7t-t^2<BR>\n" );
document.write( "s'(t) = 7 - 2t<BR>\n" );
document.write( "Speed is decreasing when s'(t) < 0<BR>\n" );
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document.write( "At t=4, speed = -1, which is \"moving left\" if left is defined as decreasing.<BR>\n" );
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document.write( "Another poorly written problem.\r<BR>\n" );
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document.write( "A. t=0 B. t=1 C. t=2 D. t=7/2 E. t= 4 </SPAN>\n" );
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