Nuprl Lemma : real-fun-implies-sfun-general

[I:Interval]. ∀[f:I ⟶ℝ].
  ∀x,y:{x:ℝx ∈ I} .  (f x ≠  x ≠ y) supposing ∀x,y:{x:ℝx ∈ I} .  ((x y)  ((f x) (f y)))


Proof




Definitions occuring in Statement :  rfun: I ⟶ℝ i-member: r ∈ I interval: Interval rneq: x ≠ y req: y real: uimplies: supposing a uall: [x:A]. B[x] all: x:A. B[x] implies:  Q set: {x:A| B[x]}  apply: a
Definitions unfolded in proof :  uall: [x:A]. B[x] uimplies: supposing a member: t ∈ T all: x:A. B[x] implies:  Q rfun: I ⟶ℝ prop: so_lambda: λ2x.t[x] so_apply: x[s] or: P ∨ Q not: ¬A guard: {T} false: False iff: ⇐⇒ Q and: P ∧ Q sq_stable: SqStable(P) squash: T subtype_rel: A ⊆B top: Top cand: c∧ B subinterval: I ⊆  uiff: uiff(P;Q) rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced :  req_witness i-member_wf req_wf real_wf real-weak-Markov rneq_wf set_wf all_wf rfun_wf interval_wf rneq-cases not_wf rneq_irreflexivity rneq_functionality req_weakening rmin-rmax-subinterval sq_stable__i-member rmin-rleq-rmax rmin_wf rmax_wf equal_wf member_rccint_lemma rleq_wf rmin_ub rleq-rmax rmin-rleq rccint_wf rmax_lb req_functionality rmin_functionality rmax_functionality rmin-req rmax-req
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation cut introduction sqequalRule sqequalHypSubstitution lambdaEquality dependent_functionElimination thin hypothesisEquality extract_by_obid isectElimination applyEquality setElimination rename dependent_set_memberEquality hypothesis because_Cache independent_functionElimination setEquality lambdaFormation independent_isectElimination functionEquality unionElimination inlFormation inrFormation voidElimination productElimination imageMemberEquality baseClosed imageElimination equalityTransitivity equalitySymmetry isect_memberEquality voidEquality independent_pairFormation productEquality

Latex:
\mforall{}[I:Interval].  \mforall{}[f:I  {}\mrightarrow{}\mBbbR{}].
    \mforall{}x,y:\{x:\mBbbR{}|  x  \mmember{}  I\}  .    (f  x  \mneq{}  f  y  {}\mRightarrow{}  x  \mneq{}  y) 
    supposing  \mforall{}x,y:\{x:\mBbbR{}|  x  \mmember{}  I\}  .    ((x  =  y)  {}\mRightarrow{}  ((f  x)  =  (f  y)))



Date html generated: 2017_10_03-AM-09_57_00
Last ObjectModification: 2017_08_31-AM-11_52_29

Theory : reals


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