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How to Calculate Factorials
Formula
A factorial n! is the product of all positive integers from 1 to n. For example, 6! = 720.
By convention, 0! = 1. Factorials grow extremely fast and are fundamental in combinatorics and probability.
Common use cases:
- Counting permutations and combinations
- Probability distribution calculations
- Taylor series expansion terms
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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