V = pi·r^2·h --> h = V/(pi·r^2)
O = 2·pi·(r^2 + h·r)
O = 2·pi·(r^2 + V/(pi·r^2)·r)
O = 2·pi·(r^2 + V/(pi·r))
O' = 2·pi·(2·r - v/(pi·r^2)) = 0 --> r = (V/(2·pi))^{1/3}
h = (8·V/pi)^{1/3}
Bei dir
r = (1/(2·pi))^{1/3} = 0.5419 dm = 5.419 cm
h = (8·1/pi)^{1/3} = 1.366 dm = 13.66 cm