Counting and Probability
Binomial Theorem
(x+y)^n = Σ C(n,k) x^(n−k) y^k; yields coefficients for polynomial expansions and is the basis for many combinatorial identities.
0
Contest appearances
100
Practice problems
1–10
Difficulty levels
Drill this topic
Sign in and tell the coach to drill this knowledge point — it picks questions matched to your current level.