建议a2之类的 最好写成a² 或者写成x^2 ,以便于判别和解题(a²-3a+2)x²+(2a²-4a+1)xy+(a²-a)y²＝(a-1)(a-2)x²+(2a²-4a+1)xy+a(a-1)y²=[(a-1)x+ay]*[(a-2)x+(a-1)y]...