Nuprl Lemma : rnexp2-positive

∀x:ℝ. (x ≠ r0 ⇒ (r0 < x^2))


Proof




Definitions occuring in Statement :  rneq: x ≠ y,  rless: x < y,  rnexp: x^k1,  int-to-real: r(n),  real: ℝ,  all: ∀x:A. B[x],  implies: P ⇒ Q,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  rneq: x ≠ y,  or: P ∨ Q,  member: t ∈ T,  uall: ∀[x:A]. B[x],  prop: ℙ,  uimplies: b supposing a,  nat: ℕ,  rless: x < y,  sq_exists: ∃x:A [B[x]],  nat_plus: ℕ+,  decidable: Dec(P),  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  top: Top,  false: False,  uiff: uiff(P;Q),  and: P ∧ Q,  req_int_terms: t1 ≡ t2,  guard: {T},  rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced :  rneq_wf,  int-to-real_wf,  real_wf,  rnexp-positive,  rminus_wf,  rless-implies-rless,  nat_plus_properties,  decidable__le,  full-omega-unsat,  intformnot_wf,  intformle_wf,  itermConstant_wf,  istype-int,  int_formula_prop_not_lemma,  istype-void,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_formula_prop_wf,  istype-le,  rsub_wf,  itermSubtract_wf,  itermVar_wf,  itermMinus_wf,  req-iff-rsub-is-0,  real_polynomial_null,  real_term_value_sub_lemma,  real_term_value_const_lemma,  real_term_value_var_lemma,  real_term_value_minus_lemma,  rless_transitivity1,  rnexp_wf,  rleq_weakening,  req_functionality,  rmul_wf,  rnexp2,  itermMultiply_wf,  real_term_value_mul_lemma
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  sqequalHypSubstitution,  unionElimination,  thin,  universeIsType,  cut,  introduction,  extract_by_obid,  isectElimination,  hypothesisEquality,  natural_numberEquality,  hypothesis,  dependent_functionElimination,  independent_functionElimination,  because_Cache,  independent_isectElimination,  dependent_set_memberEquality_alt,  setElimination,  rename,  approximateComputation,  dependent_pairFormation_alt,  lambdaEquality_alt,  isect_memberEquality_alt,  voidElimination,  sqequalRule,  productElimination,  int_eqEquality

Latex:
\mforall{}x:\mBbbR{}.  (x  \mneq{}  r0  {}\mRightarrow{}  (r0  <  x\^{}2))



Date html generated: 2019_10_29-AM-09_39_41
Last ObjectModification: 2019_03_20-PM-00_17_13

Theory : reals


Home Index