11 lines
294 B
Text
11 lines
294 B
Text
import logic
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open tactic
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theorem tst (a b : Prop) (H : ¬ a ∨ ¬ b) (Hb : b) : ¬ a ∧ b
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:= by apply and.intro;
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assumption;
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apply not_intro;
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exact
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(assume Ha, or.elim H
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(assume Hna, @absurd _ false Ha Hna)
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(assume Hnb, @absurd _ false Hb Hnb))
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