9 lines
270 B
Text
9 lines
270 B
Text
example (p q r : Prop) : p ∧ q ∧ r → q ∧ p :=
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assume Hpqr : p ∧ q ∧ r,
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have Hp : p, from and.elim_left Hpqr,
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have Hqr : q ∧ r, from and.elim_right Hpqr,
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have Hq : q, from and.elim_left Hqr,
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show q ∧ p, from
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proof
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and.intro Hq Hp
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qed
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