计算:(a/a-b-a²/a²-2ab+b²)÷(a/a+b-a²/a²
计算 (a²-2ab+b²-a+b)÷(a-b) (a+b)²÷(a-b)
计算:a/b(a-b)-b/a(a-b);(1/a+1/b)÷a²+2ab+b²/a+b.
计算:(a²-b²)/(a+b)+(a²-2ab+b²)/(a-b)
计算:(a/a-b-a²/a²-2ab+b²)÷(a/a+b-a²/a²
化简 (a²+b²/a²-b²-a-b/a+b)÷2ab/(a-b)(a+b)&
计算3a²b²÷a²+b×(a²b-3ab-5a²b)
计算:[(a+b)(a-b)-(a+b)²]÷(a+b).过程
计算:(a-b)²(a-b)³(b-a)
计算:(a-b)(a-b)²(b-a)³
计算:(a-b)(b-a)²(a-b)³
计算:2a(a+b)-(a+b)²
先化简,再求值;[(2a-b/a+b)-(b/a-b)]÷{(a-2b/a+b)+[ab/(a-b)²]},其