求不定积分：∫(x+3)/(x^2-5x+6)dx=
问题描述：
求不定积分：∫(x+3)/(x^2-5x+6)dx=
答
∫(x+3)/(x^2-5x+6)dx=∫(x+3)/[(x-2)(x-3)]dx=∫(x-3+6)/[(x-2)(x-3)]dx=∫{1/(x-2)+6*[(x-2)-(x-3)]/[(x-2)(x-3)]}dx=∫[1/(x-2)+6/(x-3)-6/[(x-2)]dx=∫[6/(x-3)-5/[(x-2)]dx=6ln|x-3|-5ln|x-2|+C或者直接用待定...