document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=199446>Question 199446</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The height, h, in metres, of a car above the ground as a Ferris wheel turns can be modeled using the function h=15cos(pi*t/120) + 18.\r<BR>\n" );
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document.write( "Estimate a value for the instantaneous rate of change of h at t=20 s (answer is -0.196 m/s). Please show the work involved!!! Thanks in advance! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #149873 by </B><A HREF=/tutors/aboutme.mpl?userid=vleith><B>vleith(2983)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vleith><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=149873\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use this URL --> http://www44.wolframalpha.com/input/?i=15cos(pi*t%2F120)+%2B+18\r<BR>\n" );
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document.write( "Scroll down to the derivative section and click \"Show steps\". This will show you how to get the formula for the instantaneous rate of change (derivative). Now plug in t=20 to that and see what you get. :)<BR>\n" );
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