document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1122435>Question 1122435</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The distance D km between two ships A and B at time t hours is given by the formula D = 4t^2 - 36t +95. Find the minimum distance between the ships  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #738570 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=738570\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The distance D km between two ships A and B at time t hours is given by the formula D = 4t^2 - 36t +95. Find the minimum distance between the ships <BR>\n" );
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document.write( "1st derivative = 8t - 36<BR>\n" );
document.write( "8t-36 = 0<BR>\n" );
document.write( "t = 4.5 hours<BR>\n" );
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document.write( "D = 4*4.5^2 - 36*4.5 + 95<BR>\n" );
document.write( "D = 14 km<BR>\n" );
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document.write( "Without calculus:<BR>\n" );
document.write( "The closest point is the vertex of the parabola, at t = -b/2a = 36/8 = 4.5<BR>\n" );
document.write( "D = 14 kms </SPAN>\n" );
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