Nuprl Lemma : Minkowski-inequality2

∀[n:ℕ]. ∀[x,y:ℝ^n].  (||x - y|| ≤ (||x|| + ||y||))


Proof




Definitions occuring in Statement :  real-vec-norm: ||x||,  real-vec-sub: X - Y,  real-vec: ℝ^n,  rleq: x ≤ y,  radd: a + b,  nat: ℕ,  uall: ∀[x:A]. B[x]
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  rleq: x ≤ y,  rnonneg: rnonneg(x),  all: ∀x:A. B[x],  le: A ≤ B,  and: P ∧ Q,  not: ¬A,  implies: P ⇒ Q,  false: False,  subtype_rel: A ⊆r B,  real: ℝ,  prop: ℙ,  true: True,  absval: |i|,  uimplies: b supposing a,  uiff: uiff(P;Q),  squash: ↓T,  guard: {T},  iff: P ⇐⇒ Q,  rev_uimplies: rev_uimplies(P;Q),  rge: x ≥ y,  real-vec-mul: a*X,  real-vec-add: X + Y,  real-vec-sub: X - Y,  req-vec: req-vec(n;x;y),  nat: ℕ,  real-vec: ℝ^n,  rsub: x - y
Lemmas referenced :  rminus-as-rmul,  req_inversion,  req_functionality,  rminus_wf,  int_seg_wf,  real-vec-norm_functionality,  rleq_weakening,  rleq_weakening_equal,  rleq_functionality_wrt_implies,  rmul-one-both,  iff_weakening_equal,  rabs-int,  true_wf,  squash_wf,  rleq_wf,  real-vec-norm-mul,  radd_functionality,  req_weakening,  rleq_functionality,  rabs_wf,  rmul_wf,  real-vec-add_wf,  nat_wf,  real-vec_wf,  nat_plus_wf,  real_wf,  real-vec-sub_wf,  real-vec-norm_wf,  radd_wf,  rsub_wf,  less_than'_wf,  int-to-real_wf,  real-vec-mul_wf,  Minkowski-inequality1
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  minusEquality,  natural_numberEquality,  hypothesis,  sqequalRule,  lambdaEquality,  dependent_functionElimination,  productElimination,  independent_pairEquality,  because_Cache,  applyEquality,  setElimination,  rename,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  isect_memberEquality,  voidElimination,  callbyvalueReduce,  sqleReflexivity,  independent_isectElimination,  imageElimination,  imageMemberEquality,  baseClosed,  universeEquality,  independent_functionElimination,  lambdaFormation

Latex:
\mforall{}[n:\mBbbN{}].  \mforall{}[x,y:\mBbbR{}\^{}n].    (||x  -  y||  \mleq{}  (||x||  +  ||y||))



Date html generated: 2016_05_18-AM-09_50_29
Last ObjectModification: 2016_01_17-AM-02_51_51

Theory : reals


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