2012.山西 化简x^2-1/x^2-2x+1.x-1/x^2+x+2/x的结果是

问题描述:

2012.山西 化简x^2-1/x^2-2x+1.x-1/x^2+x+2/x的结果是

x^2-1/x^2-2x+1.x-1/x^2+x+2/x
=(x-1)(x+1)/(x-1)²*(x-1)/x(x+1)+2/x
=1/x+2/x
=3/x