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: y rminus: -(x) real: so_apply: x[s] all: x:A. B[x] implies:  Q function: x:A ⟶ B[x]
Definitions unfolded in proof :  all: x:A. B[x] implies:  Q member: t ∈ T so_lambda: λ2x.t[x] rfun: I ⟶ℝ uall: [x:A]. B[x] prop: so_apply: x[s] subtype_rel: A ⊆B top: Top uimplies: 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