9!-8!-7!x64
=1.2.3.....9-1.2.3....8-1.2.3...7.64
=1.2.3.....9-1.2.3...8-1.2.3....7.8.8
=1.2.3.....8(9-1-8)
=1.2.3....8.0=0
Ta có: 9!.8!-7!.64
=1.2.3....9 - 1.2.3...8 - 7!.64
=8!.(9-1)-7!.64=8!.8-7!.64=7!8^2-7!.64=7!64-7!.64=0
Tick nhé
làm đi
ai đúng cho like
ai làm dc 0 là đúng