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Today:
I'll try to "post as we go", meaning if I get questions early I'll answer them early.
Here are some first exams from years past.
Biggest problem: some of you did a ui before ei. It has to be in the order ei before ui: \[ \begin{array}{l} {1. (\forall x)P(x) \hspace{2in} hyp}\cr {2. (\exists x)P(x)' \hspace{2in} hyp}\cr {3. P(a)' \hspace{2in} 2, ei}\cr {4. P(a) \hspace{2in} 1, ui} \end{array} \] There may be only one element in the domain with property $P(a)'$ -- so pick it out of the domain first. Then you know that $a$ will have property $P(a)$, because EVERY element of the domain does.
Biggest problem is actually a small one: indent when you're in the midst of a temporary hypothesis. In a sense these "conclusions" don't have the weight of the hypotheses, say -- they're only true within the context of the temporary hypothesis. And the whole objective of a temp hyp is to get it discharged as an implication (usually).
So treat it a little like scratch work, which our author does by indenting it. It's a good idea.
Again, any single element of the domain that falsifies the antecedent renders such a wff true (and that's usually not what you mean).
Please save your work as a single pdf (lots easier for me to grade), and upload that to Canvas. Remember to keep the grader happy! You don't want a grumpy grader, trust me; they're not nearly as sympathetic!:)