“bˆ4/(a-b)²×(aˆ4+a²b²-2a³b)/ab³÷(b²-a²)/ab+b²化简（xˆ4-yˆ4）/（2x²+xy-y²）×（2x-y）/（xy-y²）÷[（x²+y²）/y]²化简

“bˆ4/(a-b)²×(aˆ4+a²b²-2a³b)/ab³÷(b²-a²)/ab+b²化简（xˆ4-yˆ4）/（2x²+xy-y²）×（2x-y）/（xy-y²）÷[（x²+y²）/y]²化简
“bˆ4/(a-b)²×(aˆ4+a²b²-2a³b)/ab³÷(b²-a²)/ab+b²
化简
（xˆ4-yˆ4）/（2x²+xy-y²）×（2x-y）/（xy-y²）÷[（x²+y²）/y]²
化简

“bˆ4/(a-b)²×(aˆ4+a²b²-2a³b)/ab³÷(b²-a²)/ab+b²化简（xˆ4-yˆ4）/（2x²+xy-y²）×（2x-y）/（xy-y²）÷[（x²+y²）/y]²化简
bˆ4/(a-b)²×(aˆ4+a²b²-2a³b)/ab³÷(b²-a²)/(ab+b²)
=[bˆ4(aˆ4+a²b²-2a³b)(ab+b²)]/[(a-b)²ab³(b²-a²)]
=-[bˆ5a²(a²+b²-2ab)(a+b)]/[(a-b)²ab³(a²-b²)]
=-[bˆ5a²(a-b)²(a+b)]/[(a-b)²ab³(a-b)(a+b)]
=-[bˆ5a²]/[ab³(a-b)]
=-[b²a]/[(a-b)]
=ab²/(b-a)