((a-b)/(a²+ab)-a/(ab+b²))÷(b²/(a³-ab²)+1/(a+1))=
1)((a-b)/(a²+ab)-a/(ab+b²))=(a-b)(ab+b²)/(a²+ab)(ab+b²)-a(a²+ab)/(a²+ab)(ab+b²)=(a²b-ab²+ab²-b³)-(a³+a²b)/(a³b+a²b²+a²b²+ab³)=(a²b-ab²+ab²-b³-a³-a²b)/ (a³b+ +2a²b²+ab³)=(-a³-b³)/(ab(a²+2ab+b²)=(-1)(a-b)(a²+ab+b²)/(ab(a+b)(a+b))
2)(b²/(a³-ab²)+1/(a+1))=(b²/(a(a²-b²)+1/(a+1))=(b²/(a(a-b)(a+b))+1/(a+1)=(b²(a+1)/(a(a-b)(a+b))(a+1)+(a(a-b)(a+b))/(a+1)(a)(a-b)(a+b))=((ab²+b²)+(a(a²-b²))/(a+1)(a)(a-b)(a+b)=(ab²+b²+a³-ab²)/(a+1)(a)(a-b)(a+b)=(a³+d²)/(a+1)(a)(a-b)(a+b)
3)(-1)(a-b)(a²+ab+b²)/(ab(a+b)(a+b))÷(a³+d²)/(a+1)(a)(a-b)(a+b)=(-1)(a-b)(a²+ab+b²)/(ab(a+b)(a+b)·(a+1)(a)(a-b)(a+b)/(a³+d²)=(-1)(a-b)(a²+ab+b²)/(b(a+b)·(a+1)(a-b)/(a³ +b²)=(-a-1)(a-b)²(a²+ab+b²)/(ab+b²)(a³+b²)=(a-b)²(-a³-a²b-ab²-a²-ab-b²)/(a⁴b+ab³+a³b²+b⁴)