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# Binomial expansion & combinatorics

Sal explains why we use the combinatorial formula for (n choose k) to expand binomial expressions. Created by Sal Khan.

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# Binomial expansion & combinatorics

Current time: 0:00Total duration: 4:15

0 energy points

Sal explains why we use the combinatorial formula for (n choose k) to expand binomial expressions. Created by Sal Khan.