1. Logic Review

2. Inductive Reasoning:
- the process of finding a general principal based
upon the evidence of many specific instances.
1) Observe the data
2) recognize the patterns
3) make generalization from observations
4) check with more examples to confirm or
refute conjecture

3. Deductive Reasoning:
- the process of reasoning from accepted
statements to a conclusion
- to reason from known facts

4. Indicate whether the following is inductive or deductive
along with whether or not it is valid
It has rained out for the past 5 days, therefore it will rain out
tomorrow.
You need pre-cal grade 12 to enter engineering in
University of Manitoba. Jenny is in engineering, therefore
she has completed pre-cal grade 12.

5. Indicate the solution set
Set A {1, 4, 6, 7, 13}
Set B {2, 4, 5, 8, 13, 15}
Set C {5, 9, 12, 15}
a) Set A and Set B
b) Set B and not set A
c) Set C and Set A
d) Set A or Set B

7. How do you know this car was built before the year
1990?
Reasoning
If the car was built before the 90's it would not have an
mp3 player in it. It does have an mp3 player in it so it
must be built after the year 1990.
1. Examine the conclusion you must prove
Built after 1990
2. Assume the opposite of what you are proving
Built before 1990
3. Use logical reasoning to develop a statement
that is contradictory to your assumption.
Need reasoning to contradict the statement built before 1990
If the car was built before the 90's it would not have an mp3 player in it. It
does have an mp3 player in it so it must be built after the year 1990.

8. Example
Prove that you were on time today
Assume you were not on time
If you were not on time then you would be
marked late.
You were not marked late, which contradicts
our assumption
Therefore, you were on time.

9. Logical Statements
Conditional If P, then Q
Converse If Q, then P
Inverse If not P, then not Q
Contrapositive If not Q, then Not P

10. If you like Pizza, then you like Cheese