document.write( "Question 880814: I was struggling with this question. Please help me dear tutor . find the height and the radius of a cylinder of volume 150cm^3 which has the least surface area . \n" ); document.write( "
Algebra.Com's Answer #531719 by Fombitz(32388)\"\" \"About 
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First find the volume of the cylinder.
\n" ); document.write( "\"V=pi%2AR%5E2%2AL=150\"
\n" ); document.write( "Then first the surface area of the cylinder.
\n" ); document.write( "\"SA=2%2Api%2AR%5E2%2B2%2Api%2AR%2AL\"
\n" ); document.write( "Now substitute from the volume so that the surface area is now only a function of one variable.
\n" ); document.write( "\"L=150%2F%28piR%5E2%29\"
\n" ); document.write( "So then,
\n" ); document.write( "\"SA=2%2Api%2AR%5E2%2B2%2Api%2AR%2A%28150%2F%28piR%5E2%29%29\"
\n" ); document.write( "\"SA=2%2Api%2AR%5E2%2B300%2FR\"
\n" ); document.write( "To minimize the surface area, take the derivative with respect to R and set it equal to zero.
\n" ); document.write( "\"d%28SA%29%2FdR=4%2Api%2AR-300%2FR%5E2\"
\n" ); document.write( "
\n" ); document.write( "\"R=%28175%2F%282%2Api%29%29%5E%281%2F3%29\"
\n" ); document.write( "So then you can work backwards to find L.
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