依题意
M=(m,m^3)
n=(m,lnm)
所以
|MN|=根号[(m-m)^2+(m^3-lnm)^2]
=|m^3-lnm|
设
g(x)=m^3-lnm
(3m^3-1)/m=0
m=(1/3)^(1/3)
所以|MN|MIN=1/3-ln(1/3)
依题意
M=(m,m^3)
n=(m,lnm)
所以
|MN|=根号[(m-m)^2+(m^3-lnm)^2]
=|m^3-lnm|
设
g(x)=m^3-lnm
(3m^3-1)/m=0
m=(1/3)^(1/3)
所以|MN|MIN=1/3-ln(1/3)