f'(x)=-(x-m)^2-2x(x-m)=-(x-m)(3x-m)=0,x1=m,x2=m/3,m<0,m<m/3
当X属于(-无穷大,m),f'(x)<0,f(x)单调递减,当X属于[m,m/3],f'(x)>=0,f(x)单调递增,当X属于(m/3,+无穷大),f'(x)<0,f(x)单调递减。
所以f(x)的单调递增区间为[m,m/3],f(x)的极小值为f(m)=0
f'(x)=-(x-m)^2-2x(x-m)=-(x-m)(3x-m)=0,x1=m,x2=m/3,m<0,m<m/3
当X属于(-无穷大,m),f'(x)<0,f(x)单调递减,当X属于[m,m/3],f'(x)>=0,f(x)单调递增,当X属于(m/3,+无穷大),f'(x)<0,f(x)单调递减。
所以f(x)的单调递增区间为[m,m/3],f(x)的极小值为f(m)=0