广义积分∫ln(1-x^2)dx(0到1)

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广义积分∫ln(1-x^2)dx(0到1)
广义积分∫ln(1-x^2)dx(0到1)

广义积分∫ln(1-x^2)dx(0到1)
∫ln(1-x^2)dx
=xln(1-x^2)-∫xdln(1-x^2)
=xln(1-x^2)-∫x/(1-x^2)*(-2x)dx
=xln(1-x^2)-2∫(-x^2)/(1-x^2)dx
=xln(1-x^2)-2∫(1-x^2-1)/(1-x^2)dx
=xln(1-x^2)-2∫dx+2∫1/(1-x^2)dx
=xln(1-x^2)-2∫dx+∫[1/(1-x)+1/(1+x)]dx
=xln(1-x^2)-2x+ln(1+x)-ln(1-x)+C
积分限为0≤x≤1,则
∫ln(1-x^2)dx
=[1*ln(1-1^2)-2*1+ln(1+1)-ln(1-1)]-[0*ln(1-0^2)-2*0+ln(1+0)-ln(1-0)]
=[ln0-2+ln2-ln0]-[0-0+0-0]
=ln2-2