不定积分题，这题怎么解，求思路解答过程，谢谢。 请问这个高数不定积分题解答过程中划线处是怎么转换过来的？必定...
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解如下图所示
令e^x=t,x=lnt,那麼f(t)=lnt+1
∫f(x)/x*dx=∫(lnx+1)/x*dx
=∫(lnx+1)dlnx
=1/2*ln²x+lnx+C
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