In logic, "'contraposition "'is an inference that says that a flipped : the contrapositive of P \ rightarrow Q is thus \ neg Q \ rightarrow \ neg P.
32.
It is a maximal independent set because if B U { x } is not independent for some subset B of A, then A U { x } is not independent either ( the contrapositive follows from the hereditary property ).
33.
There are several ways of deriving the formula, for example, the argument that it is wrong to blame people for things that they cannot control ( essentially phrasing the formula as the contrapositive "'cannot'implies'has no duty to'" ).
34.
Explicitly, the contrapositive of the statement " if A, then B " is " if not B, then not A . " A statement and its contrapositive are logically equivalent : if the statement is true, then its contrapositive is true, and vice versa.
35.
Explicitly, the contrapositive of the statement " if A, then B " is " if not B, then not A . " A statement and its contrapositive are logically equivalent : if the statement is true, then its contrapositive is true, and vice versa.
36.
Explicitly, the contrapositive of the statement " if A, then B " is " if not B, then not A . " A statement and its contrapositive are logically equivalent : if the statement is true, then its contrapositive is true, and vice versa.
37.
In contrapositive, this means that if ZFC proves a \ Sigma ^ 1 _ 3 sentence then that sentence is also provable in ZF . The same argument can be applied to any other principle which always holds in the constructible universe, such as the combinatorial principle ?%.
38.
An individual using RP will typically speak Standard English, although the converse or inverse is not necessarily true ( the standard language may be pronounced with a regional accent, such as a Yorkshire accent ) and the contrapositive is usually correct ( it is very unlikely that someone speaking RP would use it to speak a regional dialect, for example the Yorkshire dialect ).
39.
To prove that " if a positive integer " N " is a non-square number, its square root is irrational ", we can equivalently prove its contrapositive, that " if a positive integer " N " has a square root that is rational, then " N " is a square number ."
40.
You seem to be referring to the law of contrapositive : in simple logic, " if A then B " has the equivalent truth value of " if not-B then not-A . " So " If I knew how to do X, then I would have done it " is equivalent to " If I didn't do X, then I don't know how . " Preceding talk ) 04 : 32, 8 February 2010 ( UTC)
