19 lines
344 B
Text
19 lines
344 B
Text
import data.nat
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example (a b c : Prop) : a ∧ b ↔ b ∧ a :=
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begin
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apply iff.intro,
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{intro H,
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match H with
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end},
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{intro H,
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match H with
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end},
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end
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open nat
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example : ∀ (a b : nat), a = b → b = a
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| a a (eq.refl a) := rfl
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