State the law represented by the following proposition and prove it with the help of a truth table:

Law: Idempotent law (for OR). ORing a proposition with itself gives the same proposition: $P \lor P = P$. Truth table:

P	P	$P \lor P$
0	0	0
1	1	1

The column for $P \lor P$ is identical to the column for $P$ in every row, so $P \lor P = P$. Hence the Idempotent law is proved.