Discrete Mathematics

Question

21) S1: If P, Q, R are three compound propositions and If P does not logically equivalent to Q and Q does not logically equivalent to R then P does not logically equivalent to R
S2: If P, Q, R are three compound propositions and P ⇔ Q and Q ⇔ R then
P ⇔R
a) Only S1 b) Only S2 c) both S1 and S2 d) neither S1 nor S2

Answer 1

 "⇔" means equality in bollean logic.Its equal to EXNor.

not " ⇔" means Xor.

So, we can compare  "⇔" with "=" and  not " ⇔"  with "not equal to".

so,if (a=b)^(b=c) then a=c,hence s2 is correct.

and,if (a!=b)^(b!=c) then a!=c,may be false.for example (1!=2)^(2!=1) then 1!=1 which is false.

Comments

Good Explanation thanks a lot

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i think option D is correct