是我理解错了还是什么的,我觉得只要令t=x/(1-x^2)
原式=∫1dt=t=x/(1-x^2)就可以了啊,大概是我理解错了..呵呵
1/2*LN((1+x)/(1-x));
解答;
分解因式;1/(1-x^2)=1/2*(1/(1-x)+1/(1+x))
∫dx/(1-x^2)
=(1/2)∫[1/(1-x)+1/(1+x)]dx
=(1/2)∫dx/(1-x)+(1/2)∫dx/(x+1)
=-(1/2)∫d(-x+1)/(-x+1)+(1/2)∫dx/(x+1)
=-(1/2)ln|1-x|+(1/2)ln|1+x|+c
=(1/2)ln|(1+x)/(1-x)|+c
原理:∫dx/x=lnx+c.