document.write( "Question 233136: A cylindrical can is to have volume 300 cubic centimetres. Find its height and its
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document.write( "radius if the total surface area (and hence the total amount of material used) is minimum.
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document.write( "[The volume is given by V = r2h, and the surface area is S = 2rh + 2r2, where r is the
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document.write( "radius and h is the height. \n" );
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Algebra.Com's Answer #172178 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! A cylindrical can is to have volume 300 cubic centimetres. Find its height and its \n" ); document.write( "radius if the total surface area (and hence the total amount of material used) is minimum. \n" ); document.write( "[The volume is given by V = r2h, and the surface area is S = 2rh + 2r2, where r is the radius and h is the height. \n" ); document.write( ": \n" ); document.write( "Find h in terms of the Volume \n" ); document.write( " \n" ); document.write( "h = \n" ); document.write( ": \n" ); document.write( "Surface area \n" ); document.write( "S = \n" ); document.write( "Replace h with \n" ); document.write( "S = \n" ); document.write( "we can cancel pi*r \n" ); document.write( "S = \n" ); document.write( "S = \n" ); document.write( ": \n" ); document.write( "Plot the equation \n" ); document.write( " \n" ); document.write( "With the help of a TI83, minimum on this graph: x=3.628, (Min SA ~ 248 sq/cm) \n" ); document.write( ": \n" ); document.write( "hence r = 3.628 cm is the radius \n" ); document.write( ": \n" ); document.write( "Find the height \n" ); document.write( "h = \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check this by finding the volume with this r and h \n" ); document.write( "V = \n" ); document.write( "V = 300.00 \n" ); document.write( " \n" ); document.write( " |