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Qasim
Qasim asked in Science & MathematicsMathematics · 7 years ago

Logical equivalence?

2 Answers

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  • ?
    Lv 7
    7 years ago
    Favorite Answer

    This is the rule known as Modus Tollens. It is an axiom.

  • Qasim
    7 years ago

    How can I show that:

    p->q ≡ ~q->~p

    (without using the truth tables)

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