（2） x-3分之5-x的平方-9分之x-2+2x-6分之x-1
问题描述：
（2） x-3分之5-x的平方-9分之x-2+2x-6分之x-1
答
x-3分之5-x的平方-9分之(x-2)²+(2x-6)分之(x-1)
=18(x-3)分之[18(5-x²)-2(x-2)(x-3)+9(x-1)]
=18(x-3)分之[90-18x²-2x²+10x-12+9x-9]
=18(x-3)分之[-20x²+19x+69]
答
x-3分之5-x的平方-9分之x-2+2x-6分之x-1
=5/(x-3)-(x-2)/(x²-9)+(x-1)/2(x-3)
=(10x+30-2x+4+x²+2x-3)/2(x-3)(x+3)
=(x²+10x+31)/2(x-3)(x+3)
答
x-3分之5-x方-9分之x-2+2x-6分之x-1=5/(x-3) -(x-2)/(x^2-9) +(x-1)/2(x-3)=(10(x+3) -2(x-2)+(x-1)(x+3))/2(x+3)(x-3)=(10x+30 -2x+4+x^2+3x-x-3)/2(x+3)(x-3)=(x^2+10x+31)/2(x+3)(x-3)