3-u^2=3-3u^2+2u^2
(3-u^2)/(u^3-u)=2u/(u^2-1)-3/u
∫(3-u^2)du/(u^3-u)=∫2udu/(u^2-1)-∫3du/u=ln(u^2-1)-3lnu+c
高数积分 (3-u^2)/(u^3-u)对u不定积分~
3-u^2=3-3u^2+2u^2
(3-u^2)/(u^3-u)=2u/(u^2-1)-3/u
∫(3-u^2)du/(u^3-u)=∫2udu/(u^2-1)-∫3du/u=ln(u^2-1)-3lnu+c