Metamath Proof Explorer


Theorem climlec3

Description: Comparison of a constant to the limit of a sequence. (Contributed by Scott Fenton, 5-Jan-2018)

Ref Expression
Hypotheses climlec3.1 ⊢ 𝑍 = ( ℤ≥ ‘ 𝑀 )
climlec3.2 ⊢ ( 𝜑 → 𝑀 ∈ ℤ )
climlec3.3 ⊢ ( 𝜑 → 𝐵 ∈ ℝ )
climlec3.4 ⊢ ( 𝜑 → 𝐹 ⇝ 𝐴 )
climlec3.5 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) ∈ ℝ )
climlec3.6 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) ≤ 𝐵 )
Assertion climlec3 ( 𝜑 → 𝐴 ≤ 𝐵 )

Proof

Step Hyp Ref Expression
1 climlec3.1 ⊢ 𝑍 = ( ℤ≥ ‘ 𝑀 )
2 climlec3.2 ⊢ ( 𝜑 → 𝑀 ∈ ℤ )
3 climlec3.3 ⊢ ( 𝜑 → 𝐵 ∈ ℝ )
4 climlec3.4 ⊢ ( 𝜑 → 𝐹 ⇝ 𝐴 )
5 climlec3.5 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) ∈ ℝ )
6 climlec3.6 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) ≤ 𝐵 )
7 3 renegcld ⊢ ( 𝜑 → - 𝐵 ∈ ℝ )
8 0cnd ⊢ ( 𝜑 → 0 ∈ ℂ )
9 1 fvexi ⊢ 𝑍 ∈ V
10 9 mptex ⊢ ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ∈ V
11 10 a1i ⊢ ( 𝜑 → ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ∈ V )
12 5 recnd ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) ∈ ℂ )
13 eqid ⊢ ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) = ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) )
14 fveq2 ⊢ ( 𝑚 = 𝑘 → ( 𝐹 ‘ 𝑚 ) = ( 𝐹 ‘ 𝑘 ) )
15 14 negeqd ⊢ ( 𝑚 = 𝑘 → - ( 𝐹 ‘ 𝑚 ) = - ( 𝐹 ‘ 𝑘 ) )
16 simpr ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → 𝑘 ∈ 𝑍 )
17 5 renegcld ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → - ( 𝐹 ‘ 𝑘 ) ∈ ℝ )
18 13 15 16 17 fvmptd3 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ‘ 𝑘 ) = - ( 𝐹 ‘ 𝑘 ) )
19 df-neg ⊢ - ( 𝐹 ‘ 𝑘 ) = ( 0 − ( 𝐹 ‘ 𝑘 ) )
20 18 19 eqtrdi ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ‘ 𝑘 ) = ( 0 − ( 𝐹 ‘ 𝑘 ) ) )
21 1 2 4 8 11 12 20 climsubc2 ⊢ ( 𝜑 → ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ⇝ ( 0 − 𝐴 ) )
22 df-neg ⊢ - 𝐴 = ( 0 − 𝐴 )
23 21 22 breqtrrdi ⊢ ( 𝜑 → ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ⇝ - 𝐴 )
24 18 17 eqeltrd ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ‘ 𝑘 ) ∈ ℝ )
25 3 adantr ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → 𝐵 ∈ ℝ )
26 5 25 lenegd ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( ( 𝐹 ‘ 𝑘 ) ≤ 𝐵 ↔ - 𝐵 ≤ - ( 𝐹 ‘ 𝑘 ) ) )
27 6 26 mpbid ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → - 𝐵 ≤ - ( 𝐹 ‘ 𝑘 ) )
28 27 18 breqtrrd ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → - 𝐵 ≤ ( ( 𝑚 ∈ 𝑍 ↦ - ( 𝐹 ‘ 𝑚 ) ) ‘ 𝑘 ) )
29 1 2 7 23 24 28 climlec2 ⊢ ( 𝜑 → - 𝐵 ≤ - 𝐴 )
30 1 2 4 5 climrecl ⊢ ( 𝜑 → 𝐴 ∈ ℝ )
31 30 3 lenegd ⊢ ( 𝜑 → ( 𝐴 ≤ 𝐵 ↔ - 𝐵 ≤ - 𝐴 ) )
32 29 31 mpbird ⊢ ( 𝜑 → 𝐴 ≤ 𝐵 )