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 = ( ℤ𝑀 )
climlec3.2 ( 𝜑𝑀 ∈ ℤ )
climlec3.3 ( 𝜑𝐵 ∈ ℝ )
climlec3.4 ( 𝜑𝐹𝐴 )
climlec3.5 ( ( 𝜑𝑘𝑍 ) → ( 𝐹𝑘 ) ∈ ℝ )
climlec3.6 ( ( 𝜑𝑘𝑍 ) → ( 𝐹𝑘 ) ≤ 𝐵 )
Assertion climlec3 ( 𝜑𝐴𝐵 )

Proof

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