DISCRETE MATH: LECTURE 1
DR. DANIEL FREEMAN
1. In the Beginning...aka Chapter 1.1
1.1. The Trinity.
โขAUniversal Statement says that a certain property is true for all elements in a
set. (for all )
โขAConditional Statement is an if-then statement, that is, if one thing is true
then some other thing is also true. (if-then)
โขAExistential Statement says that there is at least one thing for which the
property is true. (there exists)
1.2. The Trinity Remix.
โขUniversal Conditional Statements are both universal and conditional.
For example: For all animals a, if ais a dog, then ais a mammal.
Your example:
โขUniversal Existential Statements are universal because the first part of the
statement says that a certain property is true for all objects of a given type, and it
is existential because its second part asserts the existence of something.
For example: Every real number has an additive inverse.
Your example:
1
