• Boinkage@lemmy.world
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    10 months ago

    No. It is equal to “if not B, then not A.” You’re welcome for doing your logic 101 homework for you.

    • XeroxCool@lemmy.world
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      10 months ago

      Edit: I see the error in my below response. I leave wrong answers for conversational completeness

      That’s not equivalent either. “if not b, then not a” works if it’s a sequence but doesn’t work for options in which multiple inputs can lead to the same output. If you get pizza every Tuesday and Friday, then answering “what’s for lunch” with “if Tuesday, then pizza” and “if Friday, then pizza” doesn’t let it work in reverse. “what day is it” can’t be answered with “if pizza lunch, then Tuesday”

      • Boinkage@lemmy.world
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        10 months ago

        Ya wrong.

        If Tuesday, then pizza. And, if Friday, then pizza.

        The contrapositive : if not pizza, then not Tuesday and not Friday.

        What day is it? We’re not having pizza. So it’s not Tuesday or Friday.

        Google contrapositives then holla back

    • monotremata@kbin.social
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      10 months ago

      Honestly what the homework is probably looking for is that it’s equivalent to “B or not A.” But yeah.