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महाराष्ट्र राज्य शिक्षण मंडळएचएससी वाणिज्य (इंग्रजी माध्यम) इयत्ता १२ वी

What is tautology? What is contradiction? Show that the negation of a tautology is a contradiction and the negation of a contradiction is a tautology. - Mathematics and Statistics

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प्रश्न

What is tautology? What is contradiction?
Show that the negation of a tautology is a contradiction and the negation of a contradiction is a tautology.

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उत्तर

  • Tautology:
    A statement pattern having truth value always T, irrespective of the truth values of its component statement is called a tautology.
  • Contradiction:
    A statement pattern having truth value always F, irrespective of the truth values of its component statement is called a contradiction.

Let Statement p tautology. Consider, truth table

p ~ p
T F

i.e., negation of tautology is contradiction.
Let statement of contradiction. Consider, truth table

q ~ q
F T

i.e., negation of contradiction is tautology.

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पाठ 1: Mathematical Logic - Miscellaneous Exercise 1 [पृष्ठ ३३]

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बालभारती Mathematics and Statistics 1 (Commerce) [English] Standard 12 Maharashtra State Board
पाठ 1 Mathematical Logic
Miscellaneous Exercise 1 | Q 4.12 | पृष्ठ ३३

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