Nuprl Lemma : rcos_wf1

[x:ℝ]. (rcos(x) ∈ {y:ℝcosine(x) y} )


Proof




Definitions occuring in Statement :  rcos: rcos(x) cosine: cosine(x) req: y real: uall: [x:A]. B[x] member: t ∈ T set: {x:A| B[x]} 
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T all: x:A. B[x] so_lambda: λ2x.t[x] rfun: I ⟶ℝ prop: so_apply: x[s] implies:  Q uimplies: supposing a uiff: uiff(P;Q) and: P ∧ Q rev_uimplies: rev_uimplies(P;Q) nat: le: A ≤ B less_than': less_than'(a;b) false: False not: ¬A rcos: rcos(x) subtype_rel: A ⊆B guard: {T} squash: T true: True iff: ⇐⇒ Q rev_implies:  Q
Lemmas referenced :  approx-arg_wf cosine_wf real_wf i-member_wf riiint_wf rminus_wf sine_wf req_functionality rminus_functionality sine_functionality req_weakening req_wf derivative-cosine false_wf le_wf subtype_rel_sets req_inversion rleq_wf squash_wf true_wf rabs-rminus int-to-real_wf iff_weakening_equal rabs-sine-rleq
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut extract_by_obid sqequalHypSubstitution dependent_functionElimination thin sqequalRule lambdaEquality isectElimination setElimination rename hypothesisEquality hypothesis setEquality because_Cache independent_functionElimination lambdaFormation independent_isectElimination productElimination dependent_set_memberEquality natural_numberEquality independent_pairFormation equalityTransitivity equalitySymmetry applyEquality axiomEquality imageElimination imageMemberEquality baseClosed universeEquality

Latex:
\mforall{}[x:\mBbbR{}].  (rcos(x)  \mmember{}  \{y:\mBbbR{}|  cosine(x)  =  y\}  )



Date html generated: 2017_01_09-AM-09_10_43
Last ObjectModification: 2016_11_25-PM-09_54_37

Theory : reals_2


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