2015-03-06 16:48:48 -08:00
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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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2015-05-02 17:32:03 -07:00
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2015-03-06 16:48:48 -08:00
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end},
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{intro H,
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match H with
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2015-05-02 17:32:03 -07:00
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2015-03-06 16:48:48 -08:00
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end},
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end
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