How to write a biconditional $P\leftrightarrow Q$, into a form using only connectives: $\to, \land, \bot$ Take $P\longleftrightarrow Q$. I am struggling to understand how to rewrite this proposition as an equivalent proposition, using only the two connectives: $\;\;\to,\;\; \bot$ If someone could further explain how this can be managed thanks in advance.

$P \leftrightarrow Q$ is equivalent to :

> $(P \to Q) \land (Q \to P)$.

In turn, $A \land B$ is equivalent to :

> $(A \to (B \to \bot)) \to \bot$.