x-1分之x的平方-10x+25除x的平方-1分之5-x

x-1分之x的平方-10x+25除x的平方-1分之5-x
x-1分之x的平方-10x+25除x的平方-1分之5-x

x-1分之x的平方-10x+25除x的平方-1分之5-x
（x²-10x+25）/(x-1)÷(5-x)/(x²-1)
=（x²-10x+25）/(x-1)*(x²-1)/(5-x)
=-（x-5)²/(x-1)*(x-1)(x+1)/(x-5)
=-(x-5)(x+1)