Hey guys, the question is to negate:

$\displaystyle \sim ( \sim p \vee \sim q) \leftrightarrow (p \wedge q)$

My answer:

- $\displaystyle \sim ( \sim p \vee \sim q) \leftrightarrow (p \wedge q)$

- $\displaystyle \sim ( \sim ( \sim p \vee \sim q) \leftrightarrow (p \wedge q))$

- $\displaystyle \sim ( \sim p \vee \sim q) \leftrightarrow \sim (p \wedge q)$

- $\displaystyle \sim ( \sim p \vee \sim q) \leftrightarrow ( \sim p \vee \sim q)$

is this correct? thanks.