Nuprl Lemma : rtan_wf

∀x:{x:ℝ| x ∈ (-(π/2), π/2)} . (rtan(x) ∈ ℝ)


Proof




Definitions occuring in Statement :  rtan: rtan(x),  halfpi: π/2,  rooint: (l, u),  i-member: r ∈ I,  rminus: -(x),  real: ℝ,  all: ∀x:A. B[x],  member: t ∈ T,  set: {x:A| B[x]} 
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  rtan: rtan(x),  uall: ∀[x:A]. B[x],  uimplies: b supposing a,  rneq: x ≠ y,  guard: {T},  or: P ∨ Q,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s]
Lemmas referenced :  rcos-positive,  rdiv_wf,  rsin_wf,  rcos_wf,  rless_wf,  int-to-real_wf,  set_wf,  real_wf,  i-member_wf,  rooint_wf,  rminus_wf,  halfpi_wf
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  hypothesis,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  setElimination,  rename,  sqequalRule,  isectElimination,  because_Cache,  independent_isectElimination,  inrFormation,  natural_numberEquality,  lambdaEquality

Latex:
\mforall{}x:\{x:\mBbbR{}|  x  \mmember{}  (-(\mpi{}/2),  \mpi{}/2)\}  .  (rtan(x)  \mmember{}  \mBbbR{})



Date html generated: 2018_05_22-PM-02_59_16
Last ObjectModification: 2017_10_19-PM-05_19_05

Theory : reals_2


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