Modus Ponendo Tollens/Proof Rule/Tableau Form

Proof Rule
Let $\phi \land \psi$ be a compound statement form in a tableau proof whose main connective is the conjunction operator.

The Modus Ponendo Tollens is invoked for $\neg \left({\phi \land \psi}\right)$ in either of the two forms:


 * Form 1:


 * Form 2: