Topic Details (Notes format)

How to Use the Factorial Function (n!)

Subject: Mathematics

Book: Maths Mastery

The factorial of n, denoted n!, is the product of all positive integers up to n (e.g., 5!=120). Factorials appear in permutations, combinations (nCr = n! / [r!(n-r)!]), and expansions. For large n, the numbers grow rapidly. Factorials are key to gamma functions, probability distributions (Poisson), and combinatorial logic. Understanding them fosters quick problem-solving in arrangement tasks, advanced series expansions, or bridging to continuous extensions in advanced calculus or physics contexts.

Practice Questions

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