Nuprl Lemma : Cramers-rule

∀[r:CRng]. ∀[n:ℕ]. ∀[A:Matrix(n;n;r)]. ∀[c:{c:|r|| (c * |A|) = 1 ∈ |r|} ]. ∀[b:Column(n;r)].
  ((A*c*matrix(|matrix(if y=j then b[x,0] else A[x,y])|)) = b ∈ Column(n;r))


Proof




Definitions occuring in Statement :  matrix-scalar-mul: k*M,  matrix-det: |M|,  matrix-times: (M*N),  mx: matrix(M[x; y]),  matrix-ap: M[i,j],  matrix: Matrix(n;m;r),  nat: ℕ,  uall: ∀[x:A]. B[x],  infix_ap: x f y,  int_eq: if a=b then c else d,  set: {x:A| B[x]} ,  natural_number: $n,  equal: s = t ∈ T,  crng: CRng,  rng_one: 1,  rng_times: *,  rng_car: |r|
Definitions unfolded in proof :  true: True,  so_apply: x[s],  infix_ap: x f y,  so_lambda: λ2x.t[x],  rng: Rng,  crng: CRng,  uimplies: b supposing a,  prop: ℙ,  implies: P ⇒ Q,  not: ¬A,  false: False,  less_than': less_than'(a;b),  and: P ∧ Q,  le: A ≤ B,  nat: ℕ,  member: t ∈ T,  uall: ∀[x:A]. B[x],  squash: ↓T,  subtype_rel: A ⊆r B,  guard: {T},  iff: P ⇐⇒ Q
Lemmas referenced :  crng_wf,  nat_wf,  rng_one_wf,  matrix-det_wf,  rng_times_wf,  equal_wf,  rng_car_wf,  set_wf,  matrix_wf,  le_wf,  false_wf,  adj-solution-property,  squash_wf,  true_wf,  matrix-times_wf,  rng_wf,  adj-solution-column,  iff_weakening_equal
Rules used in proof :  applyEquality,  lambdaEquality,  because_Cache,  axiomEquality,  isect_memberEquality,  independent_isectElimination,  hypothesis,  lambdaFormation,  independent_pairFormation,  sqequalRule,  natural_numberEquality,  dependent_set_memberEquality,  hypothesisEquality,  isectElimination,  sqequalHypSubstitution,  extract_by_obid,  rename,  thin,  setElimination,  cut,  introduction,  isect_memberFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution,  imageElimination,  equalityTransitivity,  equalitySymmetry,  universeEquality,  intEquality,  imageMemberEquality,  baseClosed,  productElimination,  independent_functionElimination

Latex:
\mforall{}[r:CRng].  \mforall{}[n:\mBbbN{}].  \mforall{}[A:Matrix(n;n;r)].  \mforall{}[c:\{c:|r||  (c  *  |A|)  =  1\}  ].  \mforall{}[b:Column(n;r)].
    ((A*c*matrix(|matrix(if  y=j  then  b[x,0]  else  A[x,y])|))  =  b)



Date html generated: 2018_05_21-PM-09_40_26
Last ObjectModification: 2017_12_14-PM-04_18_11

Theory : matrices


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