1. Review
To check an argument with a tree:

2. Review To check an argument with a tree:
1. Write down the premises and the negation of the conclusion.

3. Review To check an argument with a tree:
1. Write down the premises and the negation of the conclusion.
2. Apply tree rules to every complex sentence.

4. Review To check an argument with a tree:
1. Write down the premises and the negation of the conclusion.
2. Apply tree rules to every complex sentence.
3. Mark the branches that contain contradictions as closed (*).

5. Review To check an argument with a tree:
1. Write down the premises and the negation of the conclusion.
2. Apply tree rules to every complex sentence.
3. Mark the branches that contain contradictions as closed (*).
4. If all branches are CLOSED, the argument is VALID.
If a branch is OPEN, the argument is INVALID.

6. Another Example
(P&Q)>R, P | Q>R

7. Another Example
(P&Q)>R P
-(Q>R)
(P&Q)>R, P | Q>R

8. Another Example
(P&Q)>R P
-(Q>R)
(P&Q)>R, P | Q>R

9. Another Example The (->) Rule: -(A>B) A -B (P&Q)>R P
(P&Q)>R, P | Q>R

10. Another Example The (->) Rule: -(A>B) A -B (P&Q)>R P
(P&Q)>R, P | Q>R 1

11. Another Example
(P&Q)>R P
-(Q>R) Q -R
(P&Q)>R, P | Q>R 1

12. Another Example (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R
The (>) Rule:
A>B
-A B 1

13. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R
The (>) Rule:
A>B
-A B 1
-(P&Q) R

14. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1*

15. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1*

16. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1
The (-&) Rule:
-(A&B)
-A B
-(P&Q) R *

17. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1
The (-&) Rule:
-(A&B)
-A B
-(P&Q) R *
-(A&B) =
-Av-B

18. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1
The (-&) Rule:
-(A&B)
-A B
-(P&Q) R * 3
-P -Q
-(A&B) =
-Av-B

19. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1* 3
-P -Q

20. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1* 3
-P -Q *

21. Another Example 2 (P&Q)>R P -(Q>R) Q -R (P&Q)>R, P | Q>R 1* 3
-P -Q
* *

22. For more click here Another Example 2 (P&Q)>R P -(Q>R) Q -R
VALID 1
-(P&Q) R * 3
-P -Q
* *
For more click here