Nuprl Lemma : real-Cramers-rule1

[n:ℕ]. ∀[A:ℕn ⟶ ℕn ⟶ ℝ]. ∀[c:{c:ℝ(c |A|) r1} ]. ∀[b:ℝ^n].
  (A*c*col(λj.|λx,y. if y=j then else (A y)|)) ≡ col(b)


Proof




Definitions occuring in Statement :  real-det: |M| real-matrix-scalar-mul: c*A real-matrix-times: (A*B) reqmatrix: X ≡ Y rcolumn: col(b) real-vec: ^n req: y rmul: b int-to-real: r(n) real: int_seg: {i..j-} nat: uall: [x:A]. B[x] int_eq: if a=b then else d set: {x:A| B[x]}  apply: a lambda: λx.A[x] function: x:A ⟶ B[x] natural_number: $n
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T subtype_rel: A ⊆B matrix: Matrix(n;m;r) real-ring: real-ring() rng_car: |r| pi1: fst(t) so_lambda: λ2y.t[x; y] so_apply: x[s1;s2] uimplies: supposing a nat: all: x:A. B[x] rng_times: * pi2: snd(t) rng_one: 1 infix_ap: y reqmatrix: X ≡ Y le: A ≤ B and: P ∧ Q less_than': less_than'(a;b) not: ¬A implies:  Q false: False int_seg: {i..j-} lelt: i ≤ j < k rmatrix: (a × b) real-vec: ^n less_than: a < b squash: T prop: quotient: x,y:A//B[x; y] stable: Stable{P} or: P ∨ Q uiff: uiff(P;Q) rev_uimplies: rev_uimplies(P;Q) matrix-ap: M[i,j] mx: matrix(M[x; y]) rcolumn: col(b) real-det: |M| r-list-sum: r-list-sum(L) reduce: reduce(f;k;as) list_ind: list_ind map: map(f;as) permutations-list: permutations-list(n) list-permutations equipollent-iff-list equipollent_inversion equipollent-factorial equipollent_functionality_wrt_equipollent equipollent_transitivity equipollent_weakening_ext-eq equipollent-nsub count-combinations primrec: primrec(n;b;c) primtailrec: primtailrec(n;i;b;f) matrix-times: (M*N) rng_sum: rng_sum mon_itop: Π lb ≤ i < ub. E[i] add_grp_of_rng: r↓+gp grp_op: * grp_id: e rng_plus: +r rng_zero: 0 so_lambda: λ2x.t[x] so_apply: x[s] guard: {T} sq_stable: SqStable(P)

Latex:
\mforall{}[n:\mBbbN{}].  \mforall{}[A:\mBbbN{}n  {}\mrightarrow{}  \mBbbN{}n  {}\mrightarrow{}  \mBbbR{}].  \mforall{}[c:\{c:\mBbbR{}|  (c  *  |A|)  =  r1\}  ].  \mforall{}[b:\mBbbR{}\^{}n].
    (A*c*col(\mlambda{}j.|\mlambda{}x,y.  if  y=j  then  b  x  else  (A  x  y)|))  \mequiv{}  col(b)



Date html generated: 2020_05_20-PM-00_38_04
Last ObjectModification: 2020_02_07-PM-04_38_40

Theory : reals


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