如图,右边黑色横线是怎么积分过去?求下解释步骤,谢谢了哈
d[x/√(x^2+1)]
={ [√(x^2+1) - x^2/√(x^2+1) ]/(x^2+1) } dx
={ [ (x^2+1) - x^2 ]/(x^2+1)^(3/2) } dx
= dx/(x^2+1)^(3/2)
∫ lnx/(x^2+1)^(3/2) dx
=∫ lnx d[x/√(x^2+1)]
详细过程在这里,希望能帮到你,望采纳哦