Nuprl Lemma : rabs-rinv

∀y:ℝ. (y ≠ r0 ⇒ (|rinv(y)| = rinv(|y|)))


Proof




Definitions occuring in Statement :  rneq: x ≠ y,  rabs: |x|,  rinv: rinv(x),  req: x = y,  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,  member: t ∈ T,  rneq: x ≠ y,  or: P ∨ Q,  prop: ℙ,  uall: ∀[x:A]. B[x],  uimplies: b supposing a,  itermConstant: "const",  req_int_terms: t1 ≡ t2,  false: False,  not: ¬A,  top: Top,  uiff: uiff(P;Q),  and: P ∧ Q,  guard: {T},  rev_uimplies: rev_uimplies(P;Q),  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  le: A ≤ B,  less_than': less_than'(a;b)
Lemmas referenced :  rabs-neq-zero,  rneq_wf,  int-to-real_wf,  real_wf,  rless-implies-rless,  rminus_wf,  real_term_polynomial,  itermSubtract_wf,  itermConstant_wf,  itermVar_wf,  itermMinus_wf,  real_term_value_const_lemma,  real_term_value_sub_lemma,  real_term_value_var_lemma,  real_term_value_minus_lemma,  req-iff-rsub-is-0,  rsub_wf,  rless_wf,  rabs-of-nonpos,  rleq_weakening_rless,  rabs_wf,  rinv_wf2,  req_functionality,  req_weakening,  rinv_functionality2,  rmul_reverses_rleq_iff,  rmul_wf,  rleq-int,  false_wf,  rleq_functionality,  itermMultiply_wf,  real_term_value_mul_lemma,  req_transitivity,  rmul-rinv,  rmul_preserves_req,  rabs-of-nonneg,  rmul_preserves_rleq
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  independent_functionElimination,  hypothesis,  addLevel,  unionElimination,  levelHypothesis,  isectElimination,  natural_numberEquality,  inrFormation,  because_Cache,  independent_isectElimination,  sqequalRule,  computeAll,  lambdaEquality,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  productElimination,  independent_pairFormation

Latex:
\mforall{}y:\mBbbR{}.  (y  \mneq{}  r0  {}\mRightarrow{}  (|rinv(y)|  =  rinv(|y|)))



Date html generated: 2017_10_03-AM-08_37_35
Last ObjectModification: 2017_07_28-AM-07_30_14

Theory : reals


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