1、化简:(x²+1/x²-1)-(x-2/x-1)÷(x-2/x) 有能力、知道者帮个忙,会哪个写哪个thank you

1、化简:(x²+1/x²-1)-(x-2/x-1)÷(x-2/x) =(x²+1)/(x²-1)-x/(x-1)=(x²+1-x²-x)/(x-1)=(1-x)/(x-1)=-12、定义运算☆,其规则为：a☆b=1/a-1/b,求(x-1)☆(1-x)=2/3中x的的值1/(x-1)-1/(1...第一个算错了把1、化简:(x²+1/x²-1)-(x-2/x-1)÷(x-2/x) =(x²+1)/(x²-1)-x/(x-1)=(x²+1-x²-x)/(x-1)(x+1)=(1-x)/(x-1)(x+1)=-1/(x+1)