用分部积分法求∫(1,0)ln(1+x)dx求步骤,谢谢
问题描述:
用分部积分法求∫(1,0)ln(1+x)dx
求步骤,谢谢
答
∫[0,1]ln(1+x)dx
=xln(1+x)[0,1]-∫[0,1] x/(1+x)dx
=ln2-∫[0,1] [1-1/(1+x)]dx
=ln2-[x-ln(1+x)][0,1]
=ln2-1+ln2
=2ln2-1