m³n²-m^5n²=m³n²(1-m²)=m³n²(1+m)(1-m)ax²-4a²x+4a³=a(x²-4ax+4a²)=a(x-2a)²-a³+2a²b-ab²=-a(a²-2ab+b²)=-a(a-b)...