4/(x^2-4)=3/(x^2+x-6)+2/(x^2+5x+6)
4/[(x+2)(x-2)]=3/[(x+3)(x-2)] +2/[(x+3)(x+2)]
4(x+3)=3(x+2)+2(x-2)
4x+12=3x+6+2x-4
x=10
经代入(x+3)(x-2)(x+2)≠0,解x=10合理