Answer
¬ and ∧ form a functionally complete collection of logical operators.
Work Step by Step
Given a compound proposition p.
We can write down a proposition q that is logically equivalent
to p and uses only ', /\, and V.
Now by De Morgan's law we can get rid of all the /\ 's by replacing each
occurrence of P1 /\ P2 /\ · · · /\ Pn with the equivalent proposition -.(-.pi V 'P2 V · · · V 'Pn).