求积分(x^4/(1+x^2))dx

问题描述:

求积分(x^4/(1+x^2))dx

答:
∫ [(x^4)/(1+x^2)]dx
=∫ { [(x^2-1)(x^2+1)+1] /(1+x^2) } dx
=∫ (x^2-1)+1/(1+x^2) dx
=(x^3) /3 -x+arctanx+C