答:
1)f(x)=x^2+lnx
求导:f'(x)=2x+1/x>0
f(x)是单调递增函数,在[1,e]上单调递增
x=1时取得最小值f(1)=1+0=1
x=e时取得最大值f(e)=e^2+1
2)
x>=1
设h(x)=f(x)-g(x)
=x^2+lnx-(2/3)x^3-(1/2)x^2
=-(2/3)x^3+(1/2)x^2+lnx
求导:
h'(x)=-2x^2+x+1/x
=-(2x^3-x^2-1)/x
设q(x)=2x^3-x^2-1
求导:q'(x)=6x^2-2x=2x(3x-1)>0
q(x)是增函数,q(x)>=q(1)=2-1-1=0
所以:h'(x)