一道微积分∫lnx/(1-x)²

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一道微积分∫lnx/(1-x)²
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一道微积分∫lnx/(1-x)²
一道微积分
∫lnx/(1-x)²

一道微积分∫lnx/(1-x)²
这种题目都不会?先凑微分再分部:
∫(lnx)/(1-x)² dx
= ∫(-lnx)/(1-x)² d(1-x)
= ∫lnxd[1/(1-x)]
= [1/(1-x)]lnx-∫[1/(1-x)]dlnx
= [1/(1-x)]lnx-∫[1/x(1-x)]dx
= [1/(1-x)]lnx+∫[1/(x-1)-1/x]dx
= [1/(1-x)]lnx+ln(x-1)-lnx+C
= ln(x-1)-[x/(x-1)]lnx+C

∫(ln(sinx))/sin²xdx
=-∫(lnsinx)dcotx
=-(lnsinx)cotx+∫cotxdlnsinx
=-(lnsinx)cotx+∫cot²xdx
=-(lnsinx)cotx+∫(csc²x-1)dx
=-(lnsinx)cotx-cotx-x+C
=-(lnsinx+1)cotx-x+C

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