what is a biconditional students will be able to: 1.rewrite compound sentences in conditional form...

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What is a Biconditional Students will be able to: 1. Rewrite compound sentences in conditional form 2. Find the biconditional of a conditional 3. Tell when/why a biconditional is true

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Page 1: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

What is a Biconditional

Students will be able to:1. Rewrite compound sentences in conditional form

2. Find the biconditional of a conditional3. Tell when/why a biconditional is true

Page 2: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

Why is the following statement called a hidden conditional?

“My parents get mad when I don’t do my homework”The hypothesis and a conclusion are hidden.

“If I don’t do my homework, then my parents get mad

Page 3: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

If a polygon has four sides, then the shape is a quadrilateral

p: A polygon has four sides q: The shape is a quadrilateral

If a polygon has four sides then the shape is a quadrilateral and if the shape is a

quadrilateral then the polygon has four sides

A polygon has four sides if and only if the shape is a

quadrilateral

1) Write p q in words

2) Write q p in wordsIf the shape is a quadrilateral, then the polygon has four sides( ) ( )p q q p Write in words3

)

Page 4: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

What is a biconditional?

Page 5: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

A polygon has four sides if and only if the shape is a

quadrilateral.

This type of statement is called a biconditional.

A biconditional is formed by combining two simple

statements using the words “if and only if”.

Symbol: p q

Definition:

Page 6: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

p: School is not in session q: It is the weekend.

Write the biconditional statement in words.

School is not in session if and only if it is the weekend.

p q

Page 7: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

p q p q q p

T

T

T

T

T

T

T

T

T

T T

T

F

F F

F F

F

F

F

A biconditional is true when p and qhave the same truth values

p q

General Truth Table for a BICONDITIONAL

(p q) (q p )

T T= T

F F= T

Page 8: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

p: The car stops q: There is a red light

Write the biconditional statement in words.

The car stops if and only if there is a red light

p q

This biconditional statement is FALSE because “If the car stops then there is a red light,” is not always true.

Page 9: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

p: A polygon has four right angles

q: A polygon is a square

3. Create a biconditional statement

A polygon has four right angles if and only if it is a square

1. Translate pq in wordsIf a polygon has four right angles then it is a square

2. Translate qp in words

If a polygon is a square then it has four right angles

Note: ( ) ( )p q q p p q

Page 10: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

Regents Prep Logic Website

www.regentsprep.org/Regents/math/tables/PracAnd.htm

Page 11: What is a Biconditional Students will be able to: 1.Rewrite compound sentences in conditional form 2.Find the biconditional of a conditional 3.Tell when/why

1) What is the symbol for a biconditional?

2) When is a biconditional true?