Nuprl Lemma : real-Cramers-rule

[n:ℕ]. ∀[A:ℝ(n × n)].  ∀[b:ℝ^n]. (A*col(λj.(|λx,y. if y=j then else (A y)|/|A|))) ≡ col(b) supposing |A| ≠ r0


Proof




Definitions occuring in Statement :  real-det: |M| real-matrix-times: (A*B) reqmatrix: X ≡ Y rcolumn: col(b) rmatrix: (a × b) real-vec: ^n rdiv: (x/y) rneq: x ≠ y int-to-real: r(n) nat: uimplies: supposing a uall: [x:A]. B[x] int_eq: if a=b then else d apply: a lambda: λx.A[x] natural_number: $n
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a rmatrix: (a × b) false: False implies:  Q not: ¬A rat_term_to_real: rat_term_to_real(f;t) rtermConstant: "const" rat_term_ind: rat_term_ind pi1: fst(t) true: True rtermMultiply: left "*" right rtermDivide: num "/" denom rtermVar: rtermVar(var) and: P ∧ Q pi2: snd(t) prop: reqmatrix: X ≡ Y all: x:A. B[x] nat: le: A ≤ B less_than': less_than'(a;b) int_seg: {i..j-} lelt: i ≤ j < k real-vec: ^n subtype_rel: A ⊆B less_than: a < b squash: T uiff: uiff(P;Q) rev_uimplies: rev_uimplies(P;Q) rcolumn: col(b) real-matrix-scalar-mul: c*A
Lemmas referenced :  real-Cramers-rule1 assert-rat-term-eq2 rtermMultiply_wf rtermDivide_wf rtermConstant_wf rtermVar_wf real-det_wf int-to-real_wf istype-int rdiv_wf req_wf rmul_wf req_witness real-matrix-times_wf istype-void istype-le rcolumn_wf subtype_rel_self int_seg_wf real_wf real-vec_wf rneq_wf rmatrix_wf istype-nat real-matrix-scalar-mul_wf real-matrix-times_functionality reqmatrix_functionality reqmatrix_weakening reqmatrix_inversion
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut extract_by_obid sqequalHypSubstitution isectElimination thin hypothesisEquality because_Cache natural_numberEquality hypothesis lambdaEquality_alt int_eqEquality independent_isectElimination approximateComputation sqequalRule independent_pairFormation dependent_set_memberEquality_alt universeIsType dependent_functionElimination applyEquality lambdaFormation_alt voidElimination setElimination rename productElimination inhabitedIsType functionEquality imageElimination independent_functionElimination functionIsTypeImplies isect_memberEquality_alt isectIsTypeImplies closedConclusion

Latex:
\mforall{}[n:\mBbbN{}].  \mforall{}[A:\mBbbR{}(n  \mtimes{}  n)].
    \mforall{}[b:\mBbbR{}\^{}n].  (A*col(\mlambda{}j.(|\mlambda{}x,y.  if  y=j  then  b  x  else  (A  x  y)|/|A|)))  \mequiv{}  col(b)  supposing  |A|  \mneq{}  r0



Date html generated: 2019_10_30-AM-08_22_50
Last ObjectModification: 2019_09_19-PM-01_10_24

Theory : reals


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