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{\bf Logic 1, WS 2008.
Homework 10, given Jan 15, due Jan 22.}

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1.
Prove using sequent calculus:
$$ (\exi_x P[x]) \impl Q\ \ylc\ \all_x(P[x] \impl Q) $$

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2.
Prove using sequent calculus:
$$ \exi_x(P[x] \impl Q)\ \ylc\ (\all_x P[x]) \impl Q $$

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