document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=482080>Question 482080</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Maths question help<BR>\n" );
document.write( "5.	Derive a formula for finding the Surface Area as a function of the radius, with the can still modelled as a cylinder. State your formula in simplest form.\r<BR>\n" );
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document.write( "6.	Differentiate the function and be sure to simplify your answer. Now use the derivative function to find the value of the radius when the Surface Area is a minimum, and then find the minimum Surface Area.<BR>\n" );
document.write( "Part C – Real Can\r<BR>\n" );
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document.write( "The soft drink can, however, is not actually a perfect cylinder.\r<BR>\n" );
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document.write( "8.	Repeat steps 5 and 6 in Part B, modelling the can with a double layer of metal on the top, but with a hemispherical indent in the base.\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 #330081 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=330081\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 5. Assuming that the object is a cylinder and the height is constant (b/c it's a function of the radius) we have\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE A = 2\pi r^2 + 2r\pi h\">\r<BR>\n" );
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document.write( "Since A is a function in terms of r,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \frac{dA}{dr} = 4\pi r + 2\pi h\">\r<BR>\n" );
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document.write( "Finding the minimum surface area is trivial, set r = 0. Hopefully this is what your problem meant...\r<BR>\n" );
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document.write( "You'll have to describe #8 a little more clearly, since my first thought is to double the area of the top, and maybe cut out a hemisphere on the bottom, but I am not 100% sure. Either way, just find the surface area (A) in terms of r, find dA/dr then set it to zero to find possible extrema. </SPAN>\n" );
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