Current time:0:00Total duration:11:59

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# Binomial expansion & combinatorics (old)

An old video of Sal explaining 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 (old)

Current time:0:00Total duration:11:59

0 energy points

An old video of Sal explaining why we use the combinatorial formula for (n choose k) to expand binomial expressions. Created by Sal Khan.