If the negation of an implication is a contradiction, the implication is a tautology.(adsbygoogle = window.adsbygoogle || []).push({});

Is this correct? Because if the negation is never true, then it must be a tautology...No?

For example, I am working on a problem that, after a whole bunch of other stuff, the negation of my statement is P [itex]\wedge[/itex] [itex]\neg[/itex]P [itex]\wedge\neg[/itex]Q..which is NEVER true. And because this was the negation of an implication (IE, the only time the implication is ever false), the implication is always true...

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# Is this a tautology?

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