Key Concepts & Glossary

Key Equations

Binomial Theorem (x+y)n=nk0(nk)xnkyk
(r+1)th term of a binomial expansion (nr)xnryr

Key Concepts

  • (nr) is called a binomial coefficient and is equal to C(n,r).
  • The Binomial Theorem allows us to expand binomials without multiplying.
  • We can find a given term of a binomial expansion without fully expanding the binomial.

Glossary

binomial coefficient
the number of ways to choose r objects from n objects where order does not matter; equivalent to C(n,r), denoted (nr)
binomial expansion
the result of expanding (x+y)n by multiplying
Binomial Theorem
a formula that can be used to expand any binomial