ab(a-b)+bc(b-c)+ac(a-c)
=a²b-ab²+b²c-bc²+ac(a-c)
=b(a²-c²)-b²(a-c)+ac(a-c)
=(a-c)(ab+bc-b²+ac)
ab(a-b)+bc(b-c)+ac(c-a)
=a²b-ab²+b²c-bc²-ac(a-c)
=b(a²-c²)-b²(a-c)-ac(a-c)
=(a-c)(ab+bc-b²-ac)
=(a-c)(b-c)(a-b)
ab(a-b)+bc(b-c)+ac(a-c)
=a²b-ab²+b²c-bc²+ac(a-c)
=b(a²-c²)-b²(a-c)+ac(a-c)
=(a-c)(ab+bc-b²+ac)
ab(a-b)+bc(b-c)+ac(c-a)
=a²b-ab²+b²c-bc²-ac(a-c)
=b(a²-c²)-b²(a-c)-ac(a-c)
=(a-c)(ab+bc-b²-ac)
=(a-c)(b-c)(a-b)