参考一下吧
根号下x求导不要算错了😂还有那个积分换元的时候,范围记得变哦
望采纳,谢谢
let
∫ f(x)dx =F(x) +C
∫(1->a) f(x) dx = a>0
=> F(a) -F(1) = a
∫(1->e^2) (1/√x) f(√x) dx
=[F(√x)]|(1->e^2)
=F(e)- F(1)
=e
(7) ∫<0, e^2> f(√x) dx / √x = ∫<0, e^2> f(√x) 2√xd√x / √x
= 2∫<0, e^2> f(√x) d√x (令√x = u)
= 2∫<0, e> f(u) du = 2∫<0, e> f(x) dx = 2