Nuprl Lemma : rabs-positive

∀x:ℝ. (x ≠ r0 ⇒ rpositive(|x|))


Proof




Definitions occuring in Statement :  rneq: x ≠ y,  rpositive: rpositive(x),  rabs: |x|,  int-to-real: r(n),  real: ℝ,  all: ∀x:A. B[x],  implies: P ⇒ Q,  natural_number: $n
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  top: Top,  all: ∀x:A. B[x],  implies: P ⇒ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  prop: ℙ
Lemmas referenced :  rabs-as-rmax,  rneq-zero,  rmax-positive,  rminus_wf,  rneq_wf,  int-to-real_wf,  real_wf
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  cut,  lemma_by_obid,  sqequalHypSubstitution,  sqequalTransitivity,  computationStep,  isectElimination,  thin,  isect_memberEquality,  voidElimination,  voidEquality,  hypothesis,  lambdaFormation,  dependent_functionElimination,  hypothesisEquality,  productElimination,  independent_functionElimination,  because_Cache,  natural_numberEquality

Latex:
\mforall{}x:\mBbbR{}.  (x  \mneq{}  r0  {}\mRightarrow{}  rpositive(|x|))



Date html generated: 2016_05_18-AM-07_12_50
Last ObjectModification: 2015_12_28-AM-00_40_59

Theory : reals


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