I tend to see these words a lot in Discrete Mathematics. I assumed these were just simple words until I bumped into a question.
Is the following proposition Satisfiable? Is it Valid?
$(P \rightarrow Q) \Leftrightarrow (Q \rightarrow R ) $
Then I searched in the net but in vain. So I'm asking here. What do you mean by Satisfiable and Valid? Please explain. Thanks in advance!