I know this may be a very basic question but I'm new to some of these concepts and I would just like to make sure I understand the reasoning.
The question is to say whether the following statement is true or false. If it is true, establish that it is and if it is false, provide a counterexample: If Δ and Γ are each satisfiable sets of formulae, then Δ∪Γ is a satisfiable set of formulae.
I think the answer is true but I'm having a hard time establishing why it is true.
Thanks!