34 lines
581 B
Text
34 lines
581 B
Text
open nat
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example (a : nat) : a + 0 = a :=
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by reflexivity
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example (a : Prop) : a ↔ a :=
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by reflexivity
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example (a b : Prop) : (a ↔ b) → (b ↔ a) :=
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by intros; symmetry; assumption
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example (a b c : nat) : a = b → b = c → c = a :=
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begin
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intros,
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symmetry,
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transitivity b,
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assumption
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end
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example (a b c : Prop) : (a ↔ b) → (b ↔ c) → (c ↔ a) :=
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begin
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intros,
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symmetry,
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transitivity b,
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assumption
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end
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example {A B C : Type} (a : A) (b : B) (c : C) : a == b → b == c → c == a :=
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begin
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intros,
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symmetry,
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transitivity b,
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assumption
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end
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