Binomial Coefficient Calculator

Calculate the number of combinations (nCk) - how many ways to choose k items from n.

Result:

Formula: $$ {n \choose k} = \frac{n!}{k!(n-k)!} $$

Understanding Binomial Coefficient

The binomial coefficient, denoted as nCk or $$ {n \choose k} $$ (read as "n choose k"), represents the number of ways to choose elements from a set of distinct elements without regard to the order of selection. It is fundamental in combinatorics, probability, and algebra.

Example:

For instance, if you have fruits and you want to choose , the binomial coefficient tells you how many different combinations of fruits you can pick.

Formula Breakdown:

  • n! (n factorial): Represents the number of ways to arrange all n items.
  • k! (k factorial): Represents the number of ways to arrange the chosen k items.
  • (n-k)! ((n-k) factorial): Represents the number of ways to arrange the remaining n-k items.

The formula $$ {n \choose k} = \frac{n!}{k!(n-k)!} $$ effectively divides out the arrangements within the chosen and unchosen groups, leaving only the number of unique combinations.

What is a Binomial Coefficient?

In mathematics, the binomial coefficient $$ {n \choose k} $$ (read as "n choose k") is the number of ways to choose a subset of k elements (combinations) from a set of n distinct elements. It is widely used in combinatorics, probability theory, and algebra.

The binomial coefficient is calculated using the formula: $$ {n \choose k} = \frac{n!}{k!(n-k)!} $$, where n! (n factorial) is the product of all positive integers up to n.

Use Cases: Binomial coefficients are used in various fields, including:

Example: To find out how many ways you can choose 3 students out of 5 for a committee, you would calculate $$ {5 \choose 3} $$, which equals 10.

Sources: Wikipedia | MathWorld