如题所述
∫x^3/(1+x^2)dx
=∫(x^3+x-x)/(1+x^2)dx
=∫(x^3+x)/(1+x^2)dx-∫x/(1+x^2)dx
=∫xdx-(1/2)∫2x/(1+x^2)dx
=x^2/2-(1/2)ln(1+x^2)
和过去了的昨天,强装笑脸安慰自己
Turning to her he asked," Darling, what do you see?"