13 lines
287 B
Text
13 lines
287 B
Text
import data.nat
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open nat algebra
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example (a b c : nat) : a = 2 → b = 3 → a + b + c = c + 5 :=
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begin
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intro h1 h2,
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have H : a + b = 2 + b, by rewrite h1,
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have H : a + b = 2 + 3, by rewrite -h2; exact H,
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have H : a + b = 5, from H,
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rewrite H,
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state,
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rewrite add.comm
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end
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