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Verifying statistical identities.?

Verify the following identities

sum of (-1)^k * (n choose k) as k goes from 0 to n is equal to 0

sum of k * (n choose k) as k goes from 1 to n is equal to n * 2^(n-1)

sum of (-1)^k * k * (n choose k) as k goes from 1 to n is equal to 0

Assume that n is greater than or equal to 2

Any help is much appreciated.

2 Answers

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  • 1 decade ago
    Favorite Answer

    This is something that might be able to be proved by induction. (Show it is true for 2, then assume it is true for n, show it is true for n+1)

  • 1 decade ago

    ...

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