求不定积分∫{ x^4 + [1/(3x)]-cos 2x } dx
问题描述：
求不定积分∫{ x^4 + [1/(3x)]-cos 2x } dx
∫{ x^4 + [1/(3x)]-cos 2x } dx
答
∫{x^4 + [1/(3x)]-cos 2x} dx
=∫ x^4dx +∫ [1/(3x)]dx-∫cos 2xdx
=1/5x^5+1/3ln(3x)-1/2sin2x+C(C为常数)