（x平方+3x+2分之x-1）+（2+x-x平方分之6）-（4-x平方分之10-x）=(x-1)/(x+2)(x+1)-6/(x-2)(x+1)-(x-10)/(x+2)(x-2)=[(x-1)(x-2)-6(x+2)-(x-10)(x+1)]/(x+1)(x-2)(x+2)=(x²-3x+2-6x-12-x²+9x+10)/(x+1)(x-...