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设∫(上限x^2下限0)f(t)dt=x^2(1-x^2),求f(x)

题目详情
设∫(上限x^2下限0)f(t)dt=x^2(1-x^2),求f(x)
▼优质解答
答案和解析
let
f(x)dx =dF(x)
∫(0->x^2)f(t)dt=x^2.(1-x^2)
F(x^2)-F(0)=x^2.(1-x^2)
[F(x^2)-F(0)]'=[x^2.(1-x^2)]'
2xf(x^2) = x^2(-2x) + 2x(1-x^2)
= 2x(1-2x^2)
f(x^2)=1-2x^2
f(x) =1-2x