Backward Factorial Explained with Solved Examples || University Engineering Mathematics
The "backward factorial" (or inverse factorial) answers the question: what integer x produces the factorial result x!? For example, since 5!= 5*4*3*2*1= 120 ,the backward factorial of 120 is 5. It is evaluated by iteratively dividing the number by consecutive integers. How to Calculate a Backward Factorial.
To find the inverse of a factorial for an exact integer, you repeatedly divide the number by increasing integers (starting from 2) until you reach 1.
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