Hello, I have some questions about the truth tables for impliocation and equivalence.(adsbygoogle = window.adsbygoogle || []).push({});

for implication we have:

p | q | p=> q

T | T | T

T | F | F

F | T | T

F | F | T

Here I do not understand the last two lines, how can we say that p implies q when p is false, and q is either true or false, if we only know that p is false and q is true, shouldn't p=> be unknown instead of T?

The same for p is false and q is false?, shouldn't p=>q then be unknown.

I have the same problem for equivalence:

p | q | p<=> q

T | T | T

T | F | F

F | T | F

F | F | T

Here I only have the problem with the last line when both p and q are false. How can we then say that p implies q?

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# Truth table, implication and equivalence

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