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The true and false relationship between _p and p
The true and false relationship between _p and p:

_p is the negation of a proposition, and the negation of a proposition is the negation of the truth of this proposition. The negation of the proposition is contrary to the truth of the original proposition. Let "P" be a proposition, then "non -p" is called the negation of proposition P, and "non-P" is recorded as "-P".

Whether a proposition holds or not has nothing to do with whether its negative proposition holds or not. It is easy to get a negative proposition of a question, and then deny all the conditions and conclusions. Let "if P is Q" be the original proposition, then "if P is not Q" is called the negative proposition of the original proposition.

The difference between negative proposition and negative proposition;

1. The negation of proposition is only the conclusion of negation of proposition, and the negation of proposition is the condition and conclusion of negation of original proposition. For example: "If a>0. Then A+B > The negation of the proposition "0" is "There is a >; 0, do a+b In the university (especially foreign universities) stage, the statement that "only the proposition conclusion is denied" is not necessarily correct. According to the truth table, if A is a false proposition, then (A =>b) and A => are not logically equal. Reference: The mathematics textbook of the University of Waterloo negates the proposition "If A is B" as "A but not B".

2. A proposition is completely opposite to its negative form. There is one and only one between the two. Reduction to absurdity is often used in mathematics. To prove a proposition, we only need to prove that its negative form is not valid. As for whether the negative proposition is established, it is not directly related to whether the original proposition is established.

Whether a proposition holds or not has nothing to do with whether its negative proposition holds or not. It is easy to get a negative proposition of a question, and then deny all the conditions and conclusions. Let "if P is Q" be the original proposition, then "if P is not Q" is called the negative proposition of the original proposition.