Question
Postal regulations specify that a package sent by certain shipping methods may have a combined length and girth of no more than 99 inches. Find the dimensions of a CYLINDRICAL package with the greatest volume that may be sent by this shipping method. HINT* the length plus the girth is 2pi(radius)+ length 0r 2pir+l.
Answers
bobpursley
99=L+2PI*radius
volume=PI*r^2 * L=PI r^2*(99-2PIr)
dv/dr=2PI r (99-2PIr)+PIr^2 *-2pi)
set dv/dr=0
and solve for r.
volume=PI*r^2 * L=PI r^2*(99-2PIr)
dv/dr=2PI r (99-2PIr)+PIr^2 *-2pi)
set dv/dr=0
and solve for r.