不定积分
求不定积分:arctanx/x^2 dx
分部积分法 ∫arctanx/x^2 dx =-∫arctanx d(1/x) =arctanx/x+∫1/[x(1+x^2)] dx =arctanx/x+∫[1/x-x/(1+x^2)] dx =arctanx/x+ln|x|-1/2×ln(1+x^2)+C
看图```````````
答:1、 令arctanx=t,则x=tant,dx=(sect)^2dt, ∫xe^arctanx/(1+x^2)^3/2 dx=∫[tant*e^t/(sect...详情>>
答:详情>>