Combinatorics

Lessons

Work through them in order – each builds on the one before.

1. 1

   Lesson 1High school~10 minContinue here

   What is a Factorial?

   Factorial basics and calculation

   →
2. 2

   Lesson 2High school~10 min

   Expressions with Factorials

   Computing expressions with factorials

3. 3

   Lesson 3High school~10 min

   Simplifying Factorial Expressions

   Techniques for simplifying factorial expressions

4. 4

   Lesson 4High school~10 min

   Factorial Equations

   How to solve equations with factorials

5. 5

   Lesson 5High school~10 min

   Combinations C(n,k)

   Choosing k items from n regardless of order

6. 6

   Lesson 6High school~10 min

   Permutations without Repetition

   Arranging n distinct elements in order

7. 7

   Lesson 7High school~10 min

   Permutations with Repetition

   Arranging elements where some repeat

8. 8

   Lesson 8High school~10 min

   Variations without Repetition

   Ordered selection of k from n without repetition

9. 9

   Lesson 9High school~10 min

   Variations with Repetition

   Ordered selection of k from n with repetition

10. The goal of this topic

    Once the lessons are behind you, prove you really know the topic. Three levels – easy, hard and expert.

    Mastery test

    Combinatorics

    Factorials, binomial coefficients, permutations and variations - with and without repetition.

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    • 100% required
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      Deep understanding

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