# Logic - Logically equivalent

1. Mar 9, 2012

### cristina89

Be $\alpha$ and $\beta$ two formulas of the propositional calculus, show that $\alpha$ and $\beta$ are logically equivalent if and only if ~$\alpha$ and ~$\beta$ are logically equivalent.

2. Mar 10, 2012

### SW VandeCarr

Is this a homework question? If so, it should be posted in the homework section: precalculus mathematics. In any case, you need to show your attempt at a solution.

3. Mar 10, 2012

### HallsofIvy

What is your definition of "logically equivalent"?