What happens when you apply a NOT to a universal quantifier

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If I have $\forall x: P(x)$, what is the equivalent function if I attach a not to the whole function:

$\neg (\forall x: P(x))$

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Read the statement out: not (for all x, p(x) holds). So if not for all x, there must be some x such that p(x) doesn't hold. So:

Then you have $\exists x : \lnot P(x)$.

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you'll have $$\exists x: \neg P(x)$$