Contact us
Choose a category below so we can get back to you as quickly as possible.
解 (xy^-1-x^-1y)/(x^-1+y^-1) =(x/y-y/x)/(1/x+1/y)——分子分母同時乘以xy =(x²;-y²;)/(y+x) =(x+y)(x-y)/(y+x) =x-y =2-(-1) =3
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.