原式=[(x+2)(x-2)/(x-3)(x+2)+(x+2)/(x-3)]×(x-3)/(x+1)=[(x-2)/(x-3)+(x+2)/(x-3)]×(x-3)/(x+1)=[(x-2+x+2)/(x-3)]×(x-3)/(x+1)=[2x/(x-3)]×(x-3)/(x+1)=2x/(x+1)
