Combinations

• Q: What are permutations, combinations, combinations with repetitions problems?
• Q: Whow the number of combinations is $\binom{n}{k}$.

Combinations with repetitions

https://en.wikipedia.org/wiki/Combination#Number_of_combinations_with_repetition

Exam old problems

https://www.dropbox.com/home/hse_math?preview=exam+problems+-+old.pdf

Homework

• Q: hw5 problems 62-106