Theorem: NNReal.count_const_le_le_of_tsum_le
File: Mathlib/MeasureTheory/Integral/Lebesgue.lean

Proof steps:
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ count {i | ε ≤ a i} ≤ ↑c / ↑ε
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ count {i | ↑ε ≤ (ofNNReal ∘ a) i} ≤ ↑c / ↑ε
tactic: rw [show (fun i => ε ≤ a i) = fun i => (ε : ℝ≥0∞) ≤ ((↑) ∘ a) i by
      funext i
      simp only [ENNReal.coe_le_coe, Function.comp]]
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ count {i | ↑ε ≤ (ofNNReal ∘ a) i} ≤ ↑c / ↑ε
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ ∑' (i : α), (ofNNReal ∘ a) i ≤ ↑c
tactic: apply
    ENNReal.count_const_le_le_of_tsum_le (measurable_coe_nnreal_ennreal.comp a_mble) _
      (mod_cast ε_ne_zero) (@ENNReal.coe_ne_top ε)
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ ∑' (i : α), (ofNNReal ∘ a) i ≤ ↑c
state_after: case h.e'_3
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ ∑' (i : α), (ofNNReal ∘ a) i = ↑(∑' (i : α), a i)
tactic: convert ENNReal.coe_le_coe.mpr tsum_le_c
state_before: case h.e'_3
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ ∑' (i : α), (ofNNReal ∘ a) i = ↑(∑' (i : α), a i)
state_after: case h.e'_3
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ ∑' (i : α), ↑(a i) = ↑(∑' (i : α), a i)
tactic: simp_rw [Function.comp_apply]
state_before: case h.e'_3
α : Type u_1
β : Type u_2
γ : Type u_3
δ : Type u_4
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSingletonClass α
a : α → ℝ≥0
a_mble : Measurable a
a_summable : Summable a
c : ℝ≥0
tsum_le_c : ∑' (i : α), a i ≤ c
ε : ℝ≥0
ε_ne_zero : ε ≠ 0
⊢ ∑' (i : α), ↑(a i) = ↑(∑' (i : α), a i)
state_after: no goals
tactic: rw [ENNReal.tsum_coe_eq a_summable.hasSum]