Cover fundamental counting tools # 🧭 Index - [[Binomial Theorem]] - Formula for expanding $(x+y)^n$ - [[Combinations]] - Number of ways to choose $k$ items from $n$ without order - [[Factorials]] - Product of all positive integers - [[Pascal Identity]] - Recurrence for binomial coefficients - [[Pascal Triangle]] - Triangular array of $\binom{n}{k}$ values - [[Permutations]] - Number of ordered arrangements of $k$ items from $n$