f(x)=lnx/x => xf(x)=lnx (定义域x>0)
g(x)=3/8*x^2-2x+2+xf(x)
=3/8*x^2-2x+2+lnx
g'(x)=3/4*x-2+1/x
当g'(x)≥0时,g(x)单调递增
由g'(x)=3/4*x-2+1/x≥0
解得 0
f(x)=lnx/x => xf(x)=lnx (定义域x>0)
g(x)=3/8*x^2-2x+2+xf(x)
=3/8*x^2-2x+2+lnx
g'(x)=3/4*x-2+1/x
当g'(x)≥0时,g(x)单调递增
由g'(x)=3/4*x-2+1/x≥0
解得 0