①a²+b²/a-b+2ab/b-a ②a/b-1+2a/1-b-3a/1-b 要详细过程

①a²+b²/a-b+2ab/b-a ②a/b-1+2a/1-b-3a/1-b 要详细过程
①a²+b²/a-b+2ab/b-a ②a/b-1+2a/1-b-3a/1-b 要详细过程

①a²+b²/a-b+2ab/b-a ②a/b-1+2a/1-b-3a/1-b 要详细过程
①
a²+b²/a-b+2ab/b-a
=a²+b²/a-b-2ab/a-b
=(a²+b²-2ab)/a-b
=(a-b)²/a-b
=a-b
②a/b-1+2a/1-b-3a/1-b
=a/b-1-2a/b-1+3a/b-1
=(a -2a +3a)/(b-1)
=2a/(b-1)