If-Then Statements/Converses Section 2-1
If-then statement (conditional statement) – has a condition containing a hypothesis and a conclusion. If ________________ then _______________. hypothesis conclusion
Hypothesis / Conclusion The part following the “if” – this part describes the condition necessary to have a desired conclusion. conclusion the outcome when the hypothesis is present – the part following the “then”
Converse the converse of a conditional is found by the and If p, then q – original If q, then p – converse switching hypothesis conclusion
Counterexample an example that shows a conditional statement false. Just one example proves the whole thing to be false.
Biconditional Statement When a statement and its converse are combined using “if and only if” From previous if p then q: P if and only if q is the biconditional iff – represents if and only iff.
From chapter 6 Inverse – if not p, then not q Contrapositive – if not q, then not p
Example Statement If it is a stone, then it is heavy. Converse If it is heavy, then it is a stone. Inverse If it is not a stone, then it is not heavy. Contrapositive If it is not heavy, then it is not a stone. Biconditional It is heavy if and only if it is a stone.
Example 2 If you are a ninja, then you are stealthy.