9 lines
162 B
Text
9 lines
162 B
Text
exit
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import logic
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example {A : Type} (f : A → A) (a b : A) : f a = b → f (f a) = f b :=
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begin
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intro fa_eq_b,
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refine (congr_arg f _),
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exact fa_eq_b
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end
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