求不定积分1/(x^4(1+x^2))

∫1/(x^4(1+x^2))dx
=∫(x^2+1-x^2)/(x^4(1+x^2))dx
=∫[1/x^4-1/(x^2(1+x^2)]dx
=-1/3x^(-3)-∫[1/(x^2-1/(1+x^2)]dx
=-1/3x^(-3)+1/x+arctanx+C本回答被提问者采纳