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AlexKontorovich/PrimeNumberTheoremAnd
Source indexedlemma · leanprover/lean4:v4.32.0

Metric.eannulusIoc_ofReal

PrimeNumberTheoremAnd.Mathlib.Topology.MetricSpace.Annulus · PrimeNumberTheoremAnd/Mathlib/Topology/MetricSpace/Annulus.lean:375 to 400

Mathematical statement

Exact Lean statement

lemma eannulusIoc_ofReal (hr : 0 ≤ r) :
    eannulusIoc x (ENNReal.ofReal r) (ENNReal.ofReal R) = annulusIoc x r R

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
lemma eannulusIoc_ofReal (hr : 0  r) :    eannulusIoc x (ENNReal.ofReal r) (ENNReal.ofReal R) = annulusIoc x r R := by  ext y  constructor  · intro hy    have hy' :        ENNReal.ofReal r < ENNReal.ofReal (dist y x)           ENNReal.ofReal (dist y x)  ENNReal.ofReal R := by      simpa [eannulusIoc, edist_dist, annulusIoc, mem_Ioc] using hy    have hrd : r < dist y x :=      (ENNReal.ofReal_lt_ofReal_iff_of_nonneg hr).1 hy'.1    have hpos : ¬dist y x  0 := not_le_of_gt (lt_of_le_of_lt hr hrd)    have hle : dist y x  R := by      have hle' : dist y x  R  dist y x  0 :=        (ENNReal.ofReal_le_ofReal_iff').1 hy'.2      exact hle'.resolve_right hpos    simp [annulusIoc, mem_Ioc, hrd, hle]  · intro hy    have hy' : r < dist y x  dist y x  R := by      simpa [annulusIoc, mem_Ioc] using hy    have : ENNReal.ofReal r < ENNReal.ofReal (dist y x) :=      (ENNReal.ofReal_lt_ofReal_iff_of_nonneg hr).2 hy'.1    have : (ENNReal.ofReal r < ENNReal.ofReal (dist y x))         (ENNReal.ofReal (dist y x)  ENNReal.ofReal R) :=      this, ENNReal.ofReal_le_ofReal hy'.2    simpa [eannulusIoc, edist_dist, annulusIoc, mem_Ioc] using this