Nuprl Lemma : derivative-function-rminus

∀f,f':ℝ ⟶ ℝ.
  ((∀x,y:ℝ.  ((x = y) ⇒ (f'[x] = f'[y])))
  ⇒ d(f[x])/dx = λx.f'[x] on (-∞, ∞)
  ⇒ d(f[-(x)])/dx = λx.-(f'[-(x)]) on (-∞, ∞))


Proof




Definitions occuring in Statement :  derivative: d(f[x])/dx = λz.g[z] on I,  riiint: (-∞, ∞),  req: x = y,  rminus: -(x),  real: ℝ,  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  function: x:A ⟶ B[x]
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  so_lambda: λ2x.t[x],  rfun: I ⟶ℝ,  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s],  subtype_rel: A ⊆r B,  top: Top,  uimplies: b supposing a,  label: ...$L... t,  true: True,  rfun-eq: rfun-eq(I;f;g),  r-ap: f(x),  squash: ↓T,  and: P ∧ Q,  uiff: uiff(P;Q),  rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced :  simple-chain-rule,  riiint_wf,  rminus_wf,  real_wf,  i-member_wf,  int-to-real_wf,  member_riiint_lemma,  subtype_rel_dep_function,  true_wf,  subtype_rel_self,  set_wf,  iproper-riiint,  req_weakening,  req_wf,  derivative_wf,  all_wf,  derivative-minus,  derivative-id,  rmul_wf,  derivative_functionality,  uiff_transitivity3,  squash_wf,  rminus-int,  uiff_transitivity,  req_functionality,  rmul-minus,  rmul_over_rminus,  rminus_functionality,  rmul-one-both
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesis,  sqequalRule,  lambdaEquality,  isectElimination,  setElimination,  rename,  hypothesisEquality,  setEquality,  natural_numberEquality,  because_Cache,  applyEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_isectElimination,  independent_functionElimination,  functionExtensionality,  functionEquality,  minusEquality,  imageElimination,  equalityTransitivity,  equalitySymmetry,  imageMemberEquality,  baseClosed,  productElimination

Latex:
\mforall{}f,f':\mBbbR{}  {}\mrightarrow{}  \mBbbR{}.
    ((\mforall{}x,y:\mBbbR{}.    ((x  =  y)  {}\mRightarrow{}  (f'[x]  =  f'[y])))
    {}\mRightarrow{}  d(f[x])/dx  =  \mlambda{}x.f'[x]  on  (-\minfty{},  \minfty{})
    {}\mRightarrow{}  d(f[-(x)])/dx  =  \mlambda{}x.-(f'[-(x)])  on  (-\minfty{},  \minfty{}))



Date html generated: 2016_10_26-AM-11_31_12
Last ObjectModification: 2016_09_05-AM-10_19_58

Theory : reals


Home Index