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(*      Distributivity                                   *)
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Axiom
Fmult_Fplus_distr : forall r1 r2 r3 : F, r1 * (r2 + r3) = r1 * r2 + r1 * r3.
Hint Resolve Fmult_Fplus_distr: field_hints.

Lemma Fmult_Fplus_distr_r : forall r2 r3 r1 : F, (r2 + r3) * r1 = r2 * r1 + r3 * r1.