11 lines
No EOL
267 B
Text
11 lines
No EOL
267 B
Text
Definition f(a : Bool) : Bool := not a.
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Theorem T (a b : Bool) : a \/ b => (f b) => a := _.
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apply imp_tac
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apply imp_tac
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apply disj_hyp_tac
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apply (** unfold_tac("f") **)
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apply assumption_tac
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apply absurd_tac
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done
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Show Environment 1. |