proposition: Lemma sqrt2_neq_0 : sqrt 2 <> 0.
proof: Proof. assert (Hyp : 0 < 2); [ prove_sup0 | generalize (Rlt_le 0 2 Hyp); intro H1; red; intro H2; generalize (sqrt_eq_0 2 H1 H2); intro H; absurd (2 = 0); [ discrR | assumption ] ]. Qed.
imports: Rbase Rfunctions SeqSeries Rtrigo1 R_sqrt