2014-08-25 02:58:48 +00:00
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import logic
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2014-09-05 01:41:06 +00:00
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open eq
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2014-07-19 08:55:34 +00:00
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section
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2014-10-09 14:13:06 +00:00
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variable {A : Type}
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2014-07-19 08:55:34 +00:00
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theorem T {a b : A} (H : a = b) : b = a
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:= symm H
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2014-10-09 14:13:06 +00:00
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variables x y : A
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variable H : x = y
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2014-07-19 08:55:34 +00:00
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check T H
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check T
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end
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section
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2014-10-09 14:13:06 +00:00
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variable {A : Type}
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2014-07-19 08:55:34 +00:00
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theorem T2 ⦃a b : A⦄ (H : a = b) : b = a
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:= symm H
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2014-10-09 14:13:06 +00:00
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variables x y : A
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variable H : x = y
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2014-07-19 08:55:34 +00:00
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check T2 H
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check T2
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end
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