NTA Abhyas JEE Main2020MathematicsMathematical ReasoningPractice
Which of the following is incorrect?
Options
- A~ p ⇔ ~ q ≡ p ⇔ q
- Bp ⇔ ~ q ≡ p ⇒ q
- C~ p ⇔ q ≡ ~ p ⇒ q
- D~ p ⇒ q ≡ p ∧ ~ q
Correct answer
B. p ⇔ ~ q ≡ p ⇒ q
Step-by-step solution
Option C & D are theorems Hence, C & D are correct For option A , ~ p ⇔ ~ q ≡ p ⇔ ~ ~ q ≡ p ⇔ q Hence, A is correct For option B , When p is true and q is false then p ⇔ ~ q is true and p ⇒ q is false Hence, option B is incorrect