Metamath Proof Explorer


Theorem lcmineqlem9

Description: (1-x)^(N-M) is continuous. (Contributed by metakunt, 12-May-2024)

Ref Expression
Hypotheses lcmineqlem9.1 ( 𝜑𝑀 ∈ ℕ )
lcmineqlem9.2 ( 𝜑𝑁 ∈ ℕ )
lcmineqlem9.3 ( 𝜑𝑀𝑁 )
Assertion lcmineqlem9 ( 𝜑 → ( 𝑥 ∈ ℂ ↦ ( ( 1 − 𝑥 ) ↑ ( 𝑁𝑀 ) ) ) ∈ ( ℂ –cn→ ℂ ) )

Proof

Step Hyp Ref Expression
1 lcmineqlem9.1 ( 𝜑𝑀 ∈ ℕ )
2 lcmineqlem9.2 ( 𝜑𝑁 ∈ ℕ )
3 lcmineqlem9.3 ( 𝜑𝑀𝑁 )
4 nfv 𝑥 𝜑
5 ax-1cn 1 ∈ ℂ
6 eqid ( 𝑥 ∈ ℂ ↦ ( 1 − 𝑥 ) ) = ( 𝑥 ∈ ℂ ↦ ( 1 − 𝑥 ) )
7 6 sub2cncf ( 1 ∈ ℂ → ( 𝑥 ∈ ℂ ↦ ( 1 − 𝑥 ) ) ∈ ( ℂ –cn→ ℂ ) )
8 5 7 mp1i ( 𝜑 → ( 𝑥 ∈ ℂ ↦ ( 1 − 𝑥 ) ) ∈ ( ℂ –cn→ ℂ ) )
9 1 nnzd ( 𝜑𝑀 ∈ ℤ )
10 2 nnzd ( 𝜑𝑁 ∈ ℤ )
11 znn0sub ( ( 𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ ) → ( 𝑀𝑁 ↔ ( 𝑁𝑀 ) ∈ ℕ0 ) )
12 9 10 11 syl2anc ( 𝜑 → ( 𝑀𝑁 ↔ ( 𝑁𝑀 ) ∈ ℕ0 ) )
13 3 12 mpbid ( 𝜑 → ( 𝑁𝑀 ) ∈ ℕ0 )
14 expcncf ( ( 𝑁𝑀 ) ∈ ℕ0 → ( 𝑦 ∈ ℂ ↦ ( 𝑦 ↑ ( 𝑁𝑀 ) ) ) ∈ ( ℂ –cn→ ℂ ) )
15 13 14 syl ( 𝜑 → ( 𝑦 ∈ ℂ ↦ ( 𝑦 ↑ ( 𝑁𝑀 ) ) ) ∈ ( ℂ –cn→ ℂ ) )
16 ssidd ( 𝜑 → ℂ ⊆ ℂ )
17 oveq1 ( 𝑦 = ( 1 − 𝑥 ) → ( 𝑦 ↑ ( 𝑁𝑀 ) ) = ( ( 1 − 𝑥 ) ↑ ( 𝑁𝑀 ) ) )
18 4 8 15 16 17 cncfcompt2 ( 𝜑 → ( 𝑥 ∈ ℂ ↦ ( ( 1 − 𝑥 ) ↑ ( 𝑁𝑀 ) ) ) ∈ ( ℂ –cn→ ℂ ) )