∫(2x^4+x)arctanxdx=[(2/5)x^5+(x^2/2)]arctanx -∫(2/5)x^5+(1/2)x^2dx/(1+x^2)
=[(2/5)x^5+x^2/2)]arctanx-(1/2)x+(1/2)arctanx-(1/10)x^4+(1/5)x^2-(1/5)ln(1+x^2)+C
高数不定积分题一枚,∫（2x∧4+x）arctanxdx
∫(2x^4+x)arctanxdx=[(2/5)x^5+(x^2/2)]arctanx -∫(2/5)x^5+(1/2)x^2dx/(1+x^2)
=[(2/5)x^5+x^2/2)]arctanx-(1/2)x+(1/2)arctanx-(1/10)x^4+(1/5)x^2-(1/5)ln(1+x^2)+C