x/(x^8-1)的不定积分
问题描述：
x/(x^8-1)的不定积分
答
设t=x^2 则dt=2xdx∴xdx/(x^8-1)=dt/2(t^4-1)1/(t^4-1)=(1/2)*[1/(t^2-1)-1/(t^2+1)]=(1/4)*[1/(t-1)-1/(t+1)]-(1/2)*[1/(t^2+1)]∴∫xdx/(x^8-1)=(1/8)*In(|t-1|/|t+1|)-(1/4)*arctant+C=(1/8)*In(|x^2-1|/|x^2+1|)...