| 释义 |
counterexample Let P(x) be a mathematical sentence involving a symbol x, so that, when x is a particular element of some set, P(x) is a statement that is either true or false. What may be of concern is proving or disproving that P(x) is true for all x. This can be shown to be false by producing just one particular x for which P(x) is false. Such a particular x is a counterexample. See De Morgan's Laws (in logic).
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