Presentation is loading. Please wait.

Presentation is loading. Please wait.

From conclusions by applying the laws of logic. Symbolic Notation Conditional statement If p, then qp ⟶q Converseq⟶p Biconditional p ⟷ q.

Similar presentations


Presentation on theme: "From conclusions by applying the laws of logic. Symbolic Notation Conditional statement If p, then qp ⟶q Converseq⟶p Biconditional p ⟷ q."— Presentation transcript:

1 From conclusions by applying the laws of logic

2 Symbolic Notation Conditional statement If p, then qp ⟶q Converseq⟶p Biconditional p ⟷ q

3 Let p be “the value of x is – 4” Let q be “ the square of x is 16” Write p ⟶q Write q⟶p

4 Let p be “the value of x is – 4” Let q be “ the square of x is 16” Write p ⟶q If the value of x is – 4, then the square of x is 16 Write q⟶p If the square of x is 16, then the value of x is – 4 Is p⟷q True?

5 Write the Contrapositive The negation of p “the value of x is -4” is written as ~p; meaning “the value of x is not -4” The contrapositive~q ⟶~p If the square of x is not 16, then the value of x is not -4. Is this true?

6 The inverse would be ~p ⟶~q If the value of x is not – 4, then the square of x is not 16. Is this True? Which statements are true?

7 The inverse would be ~p ⟶~q If the value of x is not – 4, then the square of x is not 16. Is this True? Which statements are true? The conditional statement and the contrapositive are both true. The converse and inverse are both false.

8 Remember the conditional and the contrapositive are equivalent statement as are the converse and the inverse.

9 Deductive Reasoning Deductive reasoning uses known facts, definitions and postulates to make a logical argument. Logical arguments follow laws and methods. Here are two laws of logical Law of Detachment and the Law of Syllogism.

10 Law of Detachment If p ⟶ q is a true conditional, then p is true and q is true. Does p always have to be TRUE!

11 Law of Detachment If p ⟶ q is a true conditional, then p is true and q is true. Does p always have to be TRUE! Yes

12 Law of Syllogism Here we have a chain is true statements linked together. If p ⟶q and q⟶r, then p⟶r

13 Law of Syllogism Here we have a chain is true statements linked together. If p ⟶q and q⟶r, then p⟶r. I go to school at Marian High school. Marian High school is in Mishawaka. I go to school in Mishawaka.

14 Is the Law of Syllogism always right?

15 Lets make some correct conclusion. If a fish swims at 68 mi/h, then it swims at 110 km/h. If a fish can swim at 110 km/h, then it is a sailfish

16 More Facts If a fish is the largest species of fish, then it is a Great White Shark If a fish weights over 2000 lbs, then it is the largest species of fish.

17 One more If a fish is the fastest species of fish, then it can reach speeds of 68 mi/h. What Conclusion can you make?

18 Homework Page 91 – 93 #8 – 20 even 24 – 34 even, 45 - 48

19 Homework Page 91 -93 #9 – 19 odd 23 – 35 odd 36 – 42 even, 49


Download ppt "From conclusions by applying the laws of logic. Symbolic Notation Conditional statement If p, then qp ⟶q Converseq⟶p Biconditional p ⟷ q."

Similar presentations


Ads by Google