Nuprl Lemma : rmul-nonneg-rabs

∀[x,y:ℝ].  (x * |y|) = |x * y| supposing r0 ≤ x


Proof




Definitions occuring in Statement :  rleq: x ≤ y,  rabs: |x|,  req: x = y,  rmul: a * b,  int-to-real: r(n),  real: ℝ,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  natural_number: $n
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  implies: P ⇒ Q,  prop: ℙ,  uiff: uiff(P;Q),  and: P ∧ Q,  rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced :  req_witness,  rmul_wf,  rabs_wf,  rleq_wf,  int-to-real_wf,  real_wf,  req_weakening,  req_functionality,  rabs-rmul,  rmul_functionality,  rabs-of-nonneg
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  independent_functionElimination,  universeIsType,  natural_numberEquality,  sqequalRule,  isect_memberEquality_alt,  because_Cache,  isectIsTypeImplies,  inhabitedIsType,  independent_isectElimination,  productElimination

Latex:
\mforall{}[x,y:\mBbbR{}].    (x  *  |y|)  =  |x  *  y|  supposing  r0  \mleq{}  x



Date html generated: 2019_10_29-AM-09_39_09
Last ObjectModification: 2019_02_13-PM-02_32_11

Theory : reals


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