16 lines
495 B
Text
16 lines
495 B
Text
open nat tactic
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example (q p : Prop) (h₁ : p) (h₂ : ¬ p) : q :=
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by contradiction
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example (q p : Prop) (h₁ : p) (h₂ : p → false) : q :=
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by do intros, contradiction
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example (q : Prop) (a b : nat) (h₁ : a + b = 0) (h₂ : ¬ a + b = 0) : q :=
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by do intros, contradiction
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example (q : Prop) (a b : nat) (h₁ : a + b = 0) (h₂ : a + b ≠ 0) : q :=
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by do intros, contradiction
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example (q : Prop) (a b : nat) (h₁ : a + b = 0) (h₂ : a + b = 0 → false) : q :=
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by contradiction
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