What is the opposite of them being different? That's what the question is asking. The answer is them being the same.
I put: (A <-> ~B)
This is the same as ~A iff B. Only true when they're different. The question didn't ask for a different way of saying the same thing. The question asked for the opposite.
If A=1 and B=0 then the truth value of ~(~A <-> ~B) is:
I put false.
The true answer is true. Your false answer is false.
The inside of the parentheses is "the same". That parentheses is only true when A and B are "the same".
When A=1 and B=0, they are not "the same". So that parentheses is false.
But there is a negation outside of the parentheses, so you flip the answer, and the final answer is true.
[–] antiracist ago
A iff B is only true when they're the same.
~A iff B is only true when A and B are different.
What is the opposite of them being different? That's what the question is asking. The answer is them being the same.
This is the same as ~A iff B. Only true when they're different. The question didn't ask for a different way of saying the same thing. The question asked for the opposite.
The true answer is true. Your false answer is false.
The inside of the parentheses is "the same". That parentheses is only true when A and B are "the same".
When A=1 and B=0, they are not "the same". So that parentheses is false.
But there is a negation outside of the parentheses, so you flip the answer, and the final answer is true.