Logical Truth via Truth Trees

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There's an exercise question in my book (Formal Logic: Its Scope and Limits by Richard Jeffrey) that asks whether or not $\forall x (\exists y Lxy \rightarrow \forall y Lyx)$ is a logical truth.

How would i set this up on the tree? My first thought was to compare this with a negated version of the statement, but that would be trivial, since it would be logically equivalent to one another anyway?

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Yes, you need to negate it for the setup. Then, if all branches close, it is a tautology, and if you get a finished and open branch, it is not a tautology.