I was wondering about ab! (a and b are integers, ! is factorial). Do we first multiply a and b then factorial the product or do we factorial the b and then multiply.
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Depends on the problem statement. Usually either (ab)!,(ab)!,a⋅b! is given so you don't need to worry. If it is ambigious, ask the composer. But I would treat this as (ab)!.
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Depends on the problem statement. Usually either (ab)!,(ab)!,a⋅b! is given so you don't need to worry. If it is ambigious, ask the composer. But I would treat this as (ab)!.
if you are referring to (a*b)! then you should multiply them first and then find the factorial.
ab! = a(b!) = ab!, and (ab)! = a!b!
If the problem states explicitly that ab is a two digit number, you should find the factorial of the two digit number. Like a=2,b=1, calculate 21!.
You are necessitated to multiply them first and then evaluate the factorial. Think of (2∗3)!=720, and 2∗3!=12. See the difference?