I know that $⊨$ symbol is entails symbol and $A⊨B$ means that if A is True then B must be True.
But I'm confused about the $⊭$ symbol. which one is it?
- $A⊭B$ means if A is true then B is False? = $A⊨¬B$
- $A⊭B$ means the Trueness of A is not any guarantee for B?
- $A⊭B$ means if A is False then B must be True? = $¬A⊨B$
thank you in advance.