document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=545126>Question 545126</A>: <I><SPAN STYLE=\"word-break: break-all;\"> At noon, the cruise ship Celebration is 60 miles due south of the cruise ship Inspiration and is sailing north at a rate of 30 mph. If the inspiration is sailing west at a rate of 20 mph, find the time at which the distance d between the ships is a minimum. What is this distance? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #355486 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=355486\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> At noon, the cruise ship Celebration is 60 miles due south of the cruise ship Inspiration and is sailing north at a rate of 30 mph. If the inspiration is sailing west at a rate of 20 mph, find the time at which the distance d between the ships is a minimum. What is this distance?<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s%28t%29+=+sqrt%28%2860+-+30t%29%5E2+%2B+%2820t%29%5E2%29+=+sqrt%281300t%5E2+-+3600t+%2B+3600%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "ds/st = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29%2A%281300t%5E2+-+3600t+%2B+3600%29%5E%28-1%2F2%29%2A%282600t+-+3600%29+=+0 ALIGN=MIDDLE  ALT=\"%281%2F2%29%2A%281300t%5E2+-+3600t+%2B+3600%29%5E%28-1%2F2%29%2A%282600t+-+3600%29+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > at min<BR>\n" );
document.write( "ds/dt = 0 @ 2600t - 3600 = 0<BR>\n" );
document.write( "--> t = 18/13 hours<BR>\n" );
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document.write( "s(18/13) = 33.282 miles min distance </SPAN>\n" );
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