How to Calculate Factorials
- 1). Write down all integer numbers from 1 to 5, separating them with the multiplication sign "x": 1 x 2 x 3 x 4 x 5.
- 2). Perform the multiplication of the numbers in the expression from left to right. Multiply "1" and "2" to get "2." Then multiply the product "2" and "3" to get" 6." Then multiply the product "6" and "4" to get "24," etc. Finally you would obtain 5!= 1 x 2 x 3 x 4 x 5=120.
- 3). Calculate the factorial of 50 using Stirling's formula. 50!= [sqrt(2 x 3.1416 x 50)] x (50/2.7183)^50=sqrt(314.16)] x (18.39)^50=3.035E64. Note that this value is rounded to the thousandth; the notation "E64" means "ten in power 64."
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