Write the rules for(i) ‘If-Then’ (implication) (⇒)

Answer»

(i) The compound statement ‘if p then q’ is implication of p and It is denoted by p → q or p ⇒ q. (read : p implication q)

Rule:

Note: If ‘p’ and then ‘q’ is small following:

p ⇒ q (i.e., p implies q)
p is sufficient condition for q
p only if q
q is necessary condition for p
~q implies ~p (i.e., ~q ⇒ ~p)
The compound statement ‘p if and only if q’ is double implication of p and It is denoted by p ⇔ q (read: p double implication q)
Rule:

Note: ‘p if and only if q’ is same as the following.

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