9a²b-3ab+a²+6a²b+ab+2a²

(9a²-6ab+b²)/(3a²-ab),其中b/a=2 a³+a²b-(4a²b+3ab²)+b³+6ab²+2b& 3ab+3b²/b(a²+2ab+b²) ×a²-b²/a-b ÷b/ 当a=-8,b=2时,3a²-ab/9a²-6ab+b²= (a+b/a-b)²×2a-2b/3a+3b÷ab/a²-b² (6a²-2a²)-(-a²+2ab+b²)-(a²-4ab+3b&# 化简 (a²+b²/a²-b²-a-b/a+b)÷2ab/(a-b)(a+b)& 3a²b+ab²-2a²b²-3ab²-3a²b+4ab&# a-(2ab-b²)/a为什么等于(a²-2ab+b²)/a 谢谢. 计算:(a²-b²)/(a+b)+(a²-2ab+b²)/（a-b) 计算:0.8a²b-6ab-1.2a²b+5ab+a²b 化简a/a-b - b-a+b + 2ab/a²-b²