by switching the truth values of the hypothesis and conclusion, it is called the contrapositive of the original statement. The contrapositive of a true conditional statement will also be true, while the contrapositive of a false conditional statement will also be false.
Contrapositives are an idea in logic which is very useful in math.We say that A implies B if whenever Statement A is true then we know that statement B is also true.So, Say that A implies B, written:A -> BThe contrapositive of this statement is:Not-B -> Not-ARemember "A implies B" means that B must be true if A is true, so if we know that B is falce, we can deduce that A couldn't be true, so it must be falce.With truth tables it can easily be shown that"A -> B" IF AND ONLY IF "Not-B -> Not-A"So when using the contrapositive, no information is lost.In math, this is often used in proofs when, while trying to demonstrate that A implies B, it is easier to show that Not-B implies Not-A and hence that A implies B.
Conditional ConnectivesThe statement `if p then q' is called a conditional statement and is written logically as p ! q.(This asserts that the truth of p guarantees the truth of q.)p ! q can also be read as `p implies q', where p is sometimes called the antecedent and qtheconsequent.Examples:p: It is raining.q: I get wet.p ! q: If it is raining, then I get wet.s: It is Sunday.w: I have to work today.s ! w: If it is Sunday, then I have to work today.»s ! w: If it is not Sunday, then I have to work today.s !»w: If it is Sunday, I do not have to work today.(s ^ p) !»w: If it is Sunday and it's raining, then I don't have to work today.To examine the truth or falsity of p ! q, suppose p and q are the following propositionsp: I win the lottery,q: I will buy you a car.Then p ! q is the statement `If I win the lottery, then I will buy you a car'.
compound
irony
by switching the truth values of the hypothesis and conclusion, it is called the contrapositive of the original statement. The contrapositive of a true conditional statement will also be true, while the contrapositive of a false conditional statement will also be false.
conditional and contrapositive + converse and inverse
conditional and contrapositive + converse and inverse
conditional and contrapositive + converse and inverse
conditional and contrapositive + converse and inverse
The statement "if not p, then not q" always has the same truth value as the conditional "if p, then q." They are logically equivalent.
Truth value
Contrapositives are an idea in logic which is very useful in math.We say that A implies B if whenever Statement A is true then we know that statement B is also true.So, Say that A implies B, written:A -> BThe contrapositive of this statement is:Not-B -> Not-ARemember "A implies B" means that B must be true if A is true, so if we know that B is falce, we can deduce that A couldn't be true, so it must be falce.With truth tables it can easily be shown that"A -> B" IF AND ONLY IF "Not-B -> Not-A"So when using the contrapositive, no information is lost.In math, this is often used in proofs when, while trying to demonstrate that A implies B, it is easier to show that Not-B implies Not-A and hence that A implies B.
Conditional ConnectivesThe statement `if p then q' is called a conditional statement and is written logically as p ! q.(This asserts that the truth of p guarantees the truth of q.)p ! q can also be read as `p implies q', where p is sometimes called the antecedent and qtheconsequent.Examples:p: It is raining.q: I get wet.p ! q: If it is raining, then I get wet.s: It is Sunday.w: I have to work today.s ! w: If it is Sunday, then I have to work today.»s ! w: If it is not Sunday, then I have to work today.s !»w: If it is Sunday, I do not have to work today.(s ^ p) !»w: If it is Sunday and it's raining, then I don't have to work today.To examine the truth or falsity of p ! q, suppose p and q are the following propositionsp: I win the lottery,q: I will buy you a car.Then p ! q is the statement `If I win the lottery, then I will buy you a car'.
negation
It's a short statement that describes a truth, or concept.It's a short statement that describes a truth, or concept.It's a short statement that describes a truth, or concept.It's a short statement that describes a truth, or concept.It's a short statement that describes a truth, or concept.It's a short statement that describes a truth, or concept.
The negation of a statement