-Kmath科数- 中考、高考、考验数学题库

计算下列不定积分
(1) $\int \dfrac {4x^{3}+3x+3}{(2x+1)^{2}}dx$.

(2) $\int \dfrac {dx}{x^{2}+x-2}$.

(3) $\dfrac {x^{3}-1}{x^{2}+x}dx$.

(4) $\int \dfrac {dx}{x(1+x^{2})}$.