Difference between revisions of "GATE2009 q24"

Revision as of 19:48, 14 July 2014

The binary operation □ is defined as follows

$P$	$Q$	$P□Q$
T	T	T
T	F	T
F	T	F
F	F	T

(A) $\neg Q □ ¬P$

(B) $P□\neg Q$

(C) $\neg P□Q$

(D) $\neg P□ \neg Q$

Solution by Happy Mittal

If we compare column of $P□ Q$ in table with $P ∨ Q$, we need both F in $3^{rd}$ row of table, and for that we need $\negQ$ instead of $Q$. So $P ∨ Q$ is equivalent to $P□\negQ$, and therefore, option (B) is correct.

@@ Line 31: / Line 31: @@
 ==={{Template:Author|Happy Mittal|{{mittalweb}} }}===
-If we compare column of $P\neg Q$ in table with $P &or; Q$, we need both F in $3^{rd}$ row of table, and for that we need
+If we compare column of $P□ Q$ in table with $P &or; Q$, we need both F in $3^{rd}$ row of table, and for that we need
 		$\negQ$ instead of $Q$. So $P &or; Q$ is equivalent to $P□\negQ$, and therefore, option <b>(B)</b> is correct.