document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=990438>Question 990438</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a candy bar is to be made out of cardboard that measures 80cm by 120cm. equal sized will be cut out of each corner, and then the ends and sides will be folded up to form a rectangular box. what size square be cut from each corner to obtain a maximum volume? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #610435 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=610435\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The volume of the rectangular box is (120-2x)(80-2x)*x cm^3<BR>\n" );
document.write( "This is (9600-400x+4x^2)*x<BR>\n" );
document.write( "V=4x^3-400x^2+9600x<BR>\n" );
document.write( "Take the first derivative and set it equal to zero<BR>\n" );
document.write( "12x^2-800x+9600=0<BR>\n" );
document.write( "4(3x^2-200x+3200)=0<BR>\n" );
document.write( "The vertex (minimizes x) is at x=200/6=33.3 cm must be cut  (33 1/3 is exact)<BR>\n" );
document.write( "The volume is 13.3*53.3*33.3 (units cm for each)<BR>\n" );
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