What is meant by tautology and fallacy? Prove that 1+Y is a tautology and 0.Y is a fallacy.

Q. What is meant by tautology and fallacy? Prove that 1+Y is a tautology and 0.Y is a fallacy.

Answer :-

Tautology:- If the result of any logical statement or expression is always TRUE or 1 for all input combinations, it is called Tautology.

Fallacy:- If the result of any logical statement or expression is always FALSE or 0 for all input combinations, it is called Fallacy.

• If we put value of Y = 0 or 1 in 1+Y, then result is always 1that's why this is tautology.
• If we put value of Y = 0 or 1 in 1.Y, then result is always 1that's why this is fallacy