设f(x)是连续函数，且f（x）=x2+2∫20f（t)dt,则f(x)=().
A: x2
B: x2-2
C: 2x
D: x2-16/9
A: x2
B: x2-2
C: 2x
D: x2-16/9
举一反三
- 设F(x)=x^2/(x）f(t)dt,其中f(x)为连续函数,则limF(X）=
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