Answer to Question #239657 in Discrete Mathematics for enKay

Question

Define the following with an example

(I) tautology

(I) proposition

Answer 1

1) tautology is the statement that is true in every possible interpretation. For example: $p\lor \lnot p$ is tautology because it is true either when p is true and $\lnot p$ is true.

2) proposition is a statement that can be examined and classified as truth or false. For example, lets assume that:

A-{lion is predator}

B-{Simba is lion)

And make next statements

C-{Simba is predator}

D-{Ben is predator}

Statement C is the proposition because it can be examined and, indeed, according to A and B, we can assume that C is equal to 1.

Statement D, on the other hand, is not a proposition because it could not be examined and classified as truth or false due to lack of information about Ben.