Question 1085775
what you can do is this:

8! = (8)7!

so you can factorize now as:

8(7!) -(7!)(2!) = 7! (8-2!) = 7! (8-2) = 7! (6) = (7)(6!)^2 =4.147,200.

there's not a rule for a! -(b!)(c!), because you need to know the relation between a and b.

another example is


10! - (7!(3!) = 10*9*8*(7!) - (7!3!) = 7!( 10*9*8-3!) = 7! (714) = 7! (2*3*7*17) = 3,598,560

@natolino_