2/a-2/b=1/(a-b)则2b/(ab)-2a/(ab)=1/(a-b)则(2b-2a)/(ab)=1/(a-b)所以2(b-a)(a-b)=ab所以-2a²+2ab-2b²=ab所以2a²+2b²=ab两边同时除以2ab,得a²/ab+b²/ab=1/2所以a/b+b/a=1/2...