1. Logic

2. Inductive Reasoning Based on patterns, observations, etc.
A counter-example must use the same hypothesis with any different conclusion.

3. Conditional Statements
Truth Values: Is false only when hypothesis is true and
conclusion is false. (If hypothesis is false, it’s still true since
you can never meet the hypothesis to get to the conclusion!)

4. * ** ** *
* **logically equivalent

5. True or False? If it’s Spring, then it’s March.
If two planes intersect, they intersect at a point.
If a cat is a bird, then donkeys can fly.

6. Deductive Reasoning
Law of Detachment
Modus Tollens
Law of Syllogism

7. Biconditionals Mostly for definitions
It’s a right angle iff it measures 90°.
If it’s a right angle, then it measures 90°.
If it measures 90°, then it’s a right angle.

8. Which Venn diagram is NOT correct?B D

11. Read the statement below.
If a quadrilateral has at least two right angles, then it is a rectangle.
Which figure is a counterexample that proves the statement is false? C A B D