18 lines
420 B
Text
18 lines
420 B
Text
axiom abs : Int → Int
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axiom abs_eq_self {a : Int }: abs a = a ↔ 0 ≤ a
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example (x : Int) : False := by
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let y := x/2
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have h : 0 ≤ y := sorry
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have : abs y = y := by
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-- generalize y = z at *
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simp (config := {zeta := false}) only [abs_eq_self.mpr h]
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sorry
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example (x : Int) : False := by
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let y := x/2
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have h : 0 ≤ y := sorry
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have : abs y = y := by
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simp only [abs_eq_self.mpr h]
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sorry
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