Prove that the set {→, ¬} is functionally complete I am not sure how to do this question. I have looked at some of the other similar questions but to no avail
I know that for a set of operators to be functionally complete, the set can be used to express all possible truth tables by combining members of the set into a Boolean expression

The implication $\to$ is defined by
$$ a\to b \equiv \neg a \vee b. $$
This means, that
$$ \neg a \to b \equiv a \vee b$$
and thus, you can express logical or using $\to$ and $\neg$. Furthermore you know de Morgans rules and you have
$$ \neg(\neg a \vee \neg b) \equiv \neg\neg a\wedge \neg\neg b = a\wedge b.$$
Thus you can express all logical operators using $\to$ and $\neg$. The set of these is known to be functionally complete.
