Nuprl Lemma : continuous_functionality_wrt_rfun-eq

I:Interval. ∀[f1,f2:I ⟶ℝ].  (rfun-eq(I;λx.f1[x];λx.f2[x])  f1[x] continuous for x ∈  f2[x] continuous for x ∈ I)


Proof




Definitions occuring in Statement :  continuous: f[x] continuous for x ∈ I rfun-eq: rfun-eq(I;f;g) rfun: I ⟶ℝ interval: Interval uall: [x:A]. B[x] so_apply: x[s] all: x:A. B[x] implies:  Q lambda: λx.A[x]
Definitions unfolded in proof :  all: x:A. B[x] uall: [x:A]. B[x] implies:  Q continuous: f[x] continuous for x ∈ I member: t ∈ T sq_exists: x:{A| B[x]} and: P ∧ Q prop: so_lambda: λ2x.t[x] nat_plus: + so_apply: x[s] rfun: I ⟶ℝ uimplies: supposing a rneq: x ≠ y guard: {T} or: P ∨ Q iff: ⇐⇒ Q rev_implies:  Q rless: x < y decidable: Dec(P) satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] false: False not: ¬A top: Top label: ...$L... t rfun-eq: rfun-eq(I;f;g) r-ap: f(x) uiff: uiff(P;Q)
Lemmas referenced :  req_weakening rsub_functionality rabs_functionality rleq_functionality interval_wf rfun_wf rfun-eq_wf continuous_wf icompact_wf nat_plus_wf int_formula_prop_wf int_term_value_var_lemma int_term_value_constant_lemma int_formula_prop_less_lemma int_formula_prop_not_lemma int_formula_prop_and_lemma itermVar_wf itermConstant_wf intformless_wf intformnot_wf intformand_wf satisfiable-full-omega-tt decidable__lt nat_plus_properties rless-int rdiv_wf i-member-approx less_than_wf real_wf all_wf int-to-real_wf rless_wf i-approx_wf i-member_wf rsub_wf rabs_wf rleq_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation isect_memberFormation sqequalHypSubstitution cut hypothesis dependent_functionElimination thin hypothesisEquality setElimination rename introduction dependent_set_memberEquality independent_pairFormation productElimination promote_hyp independent_functionElimination lemma_by_obid isectElimination because_Cache productEquality natural_numberEquality sqequalRule lambdaEquality functionEquality applyEquality independent_isectElimination inrFormation unionElimination dependent_pairFormation int_eqEquality intEquality isect_memberEquality voidElimination voidEquality computeAll setEquality

Latex:
\mforall{}I:Interval
    \mforall{}[f1,f2:I  {}\mrightarrow{}\mBbbR{}].
        (rfun-eq(I;\mlambda{}x.f1[x];\mlambda{}x.f2[x])  {}\mRightarrow{}  f1[x]  continuous  for  x  \mmember{}  I  {}\mRightarrow{}  f2[x]  continuous  for  x  \mmember{}  I)



Date html generated: 2016_05_18-AM-09_09_32
Last ObjectModification: 2016_01_17-AM-02_37_03

Theory : reals


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