解:
,∴
f(
x)在[0,3]上递增,·········································· 2分
证明:
f(
x+
h)-
f(
x)=
,······················· 6分
∵
x +
h,
x∈[0,3],
∴
x +
h + 1 > 0,
x + 1 > 0,························································ 8分
又∵
h > 0,
∴
f (
x +
h)-
f (
x)
> 0,········································· 9分
∴
f (
x) 在[0,3] 上递增.······················································· 10分