## Discrete Mathematics with Applications 4th Edition

Informal negation: There is at least one simple solution to life's problems. The original statement written formally with quantifiers: $\forall$ simple solutions x, x does not solve life's problems. Formal negation: $\exists$ a simple solution x, such that x solves life's problems.
The negation of a statement of the form: $\forall x \in D$, Q(x) is: $\exists x \in D$ such that ~Q(x).