（x的平方-1）分之（x的平方-2x+1）÷（x+1）分之（x的平方-x）-x分之1+x的平方
=(x²-2x+1)/(x²-1)÷(x²-x)/(x+1)-(1+x²)/x
=(x-1)²/(x+1)(x-1)÷x(x-1)/(x+1)-(1+x²)/x
=(x-1)/(x+1)×(x+1)/x(x-1)-(1+x²)/x
=1/x-(1+x²)/x
=(1-1-x²)/x
=-x
因为x=-√2
所以原式=√2