12 lines
310 B
Text
12 lines
310 B
Text
open Classical
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theorem ex : if (fun x => x + 1) = (fun x => x + 2) then False else True := by
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have : (fun x => x + 1) ≠ (fun x => x + 2) := by
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intro h
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have : 1 = 2 := congrFun h 0
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contradiction
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rw [if_neg this]
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exact True.intro
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def tst (x : Nat) : Bool :=
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if 1 < 2 then true else false
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