document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1090347>Question 1090347</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Fig. 4 shows a cone. The angle between the axis and the slant edge is 30°. Water is poured into the<BR>\n" );
document.write( "cone at a constant rate of 2 cm3 per second. At time t seconds, the radius of the water surface is r cm and the volume of water in the cone is V cm3.\r<BR>\n" );
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document.write( "Show that V= (sqrt3/3*pi*r^3) and find dv/dr<BR>\n" );
document.write( "[You may assume that the volume of a cone of height h and radius r is (1/3*pi*r^2*h)]\r<BR>\n" );
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document.write( "I worked it out but could only prove that V= sqrt3/3*pi*r^2... why would h equal (sqrt 3 r) and not just sqrt 3?\r<BR>\n" );
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document.write( "Thank you ever so much!!! \r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #704939 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=704939\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/display-illustration.mpl?tutor=Fombitz&illustration_name=cone3.png\">.<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=r%2A%28sqrt%283%29%2F3%29 ALIGN=MIDDLE  ALT=\"h=r%2A%28sqrt%283%29%2F3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So then,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=V=%28pi%2F3%29r%5E2%2Ah ALIGN=MIDDLE  ALT=\"V=%28pi%2F3%29r%5E2%2Ah\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=V=%28pi%2F3%29r%5E2%2Ar%28sqrt%283%29%2F3%29 ALIGN=MIDDLE  ALT=\"V=%28pi%2F3%29r%5E2%2Ar%28sqrt%283%29%2F3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=V=%28%28sqrt%283%29pi%29%2F9%29r%5E3 ALIGN=MIDDLE  ALT=\"V=%28%28sqrt%283%29pi%29%2F9%29r%5E3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So then differentiating,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dV%2Fdr=%28%28sqrt%283%29pi%29%2F9%293r%5E2 ALIGN=MIDDLE  ALT=\"dV%2Fdr=%28%28sqrt%283%29pi%29%2F9%293r%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dV%2Fdr=%28%28sqrt%283%29pi%29%2F3%29r%5E2 ALIGN=MIDDLE  ALT=\"dV%2Fdr=%28%28sqrt%283%29pi%29%2F3%29r%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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