Proof of Theorem cncfioobdlem
| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | cncfioobdlem.g | . . 3
⊢ 𝐺 = (𝑥 ∈ (𝐴[,]𝐵) ↦ if(𝑥 = 𝐴, 𝑅, if(𝑥 = 𝐵, 𝐿, (𝐹‘𝑥)))) | 
| 2 | 1 | a1i 11 | . 2
⊢ (𝜑 → 𝐺 = (𝑥 ∈ (𝐴[,]𝐵) ↦ if(𝑥 = 𝐴, 𝑅, if(𝑥 = 𝐵, 𝐿, (𝐹‘𝑥))))) | 
| 3 |  | cncfioobdlem.a | . . . . . . 7
⊢ (𝜑 → 𝐴 ∈ ℝ) | 
| 4 | 3 | adantr 480 | . . . . . 6
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝐴 ∈ ℝ) | 
| 5 |  | cncfioobdlem.c | . . . . . . . . . 10
⊢ (𝜑 → 𝐶 ∈ (𝐴(,)𝐵)) | 
| 6 | 3 | rexrd 11312 | . . . . . . . . . . 11
⊢ (𝜑 → 𝐴 ∈
ℝ*) | 
| 7 |  | cncfioobdlem.b | . . . . . . . . . . . 12
⊢ (𝜑 → 𝐵 ∈ ℝ) | 
| 8 | 7 | rexrd 11312 | . . . . . . . . . . 11
⊢ (𝜑 → 𝐵 ∈
ℝ*) | 
| 9 |  | elioo2 13429 | . . . . . . . . . . 11
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (𝐶 ∈ (𝐴(,)𝐵) ↔ (𝐶 ∈ ℝ ∧ 𝐴 < 𝐶 ∧ 𝐶 < 𝐵))) | 
| 10 | 6, 8, 9 | syl2anc 584 | . . . . . . . . . 10
⊢ (𝜑 → (𝐶 ∈ (𝐴(,)𝐵) ↔ (𝐶 ∈ ℝ ∧ 𝐴 < 𝐶 ∧ 𝐶 < 𝐵))) | 
| 11 | 5, 10 | mpbid 232 | . . . . . . . . 9
⊢ (𝜑 → (𝐶 ∈ ℝ ∧ 𝐴 < 𝐶 ∧ 𝐶 < 𝐵)) | 
| 12 | 11 | simp2d 1143 | . . . . . . . 8
⊢ (𝜑 → 𝐴 < 𝐶) | 
| 13 | 12 | adantr 480 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝐴 < 𝐶) | 
| 14 |  | eqcom 2743 | . . . . . . . . 9
⊢ (𝑥 = 𝐶 ↔ 𝐶 = 𝑥) | 
| 15 | 14 | biimpi 216 | . . . . . . . 8
⊢ (𝑥 = 𝐶 → 𝐶 = 𝑥) | 
| 16 | 15 | adantl 481 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝐶 = 𝑥) | 
| 17 | 13, 16 | breqtrd 5168 | . . . . . 6
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝐴 < 𝑥) | 
| 18 | 4, 17 | gtned 11397 | . . . . 5
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝑥 ≠ 𝐴) | 
| 19 | 18 | neneqd 2944 | . . . 4
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → ¬ 𝑥 = 𝐴) | 
| 20 | 19 | iffalsed 4535 | . . 3
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → if(𝑥 = 𝐴, 𝑅, if(𝑥 = 𝐵, 𝐿, (𝐹‘𝑥))) = if(𝑥 = 𝐵, 𝐿, (𝐹‘𝑥))) | 
| 21 |  | simpr 484 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝑥 = 𝐶) | 
| 22 | 5 | elioored 45567 | . . . . . . . 8
⊢ (𝜑 → 𝐶 ∈ ℝ) | 
| 23 | 22 | adantr 480 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝐶 ∈ ℝ) | 
| 24 | 21, 23 | eqeltrd 2840 | . . . . . 6
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝑥 ∈ ℝ) | 
| 25 | 11 | simp3d 1144 | . . . . . . . 8
⊢ (𝜑 → 𝐶 < 𝐵) | 
| 26 | 25 | adantr 480 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝐶 < 𝐵) | 
| 27 | 21, 26 | eqbrtrd 5164 | . . . . . 6
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝑥 < 𝐵) | 
| 28 | 24, 27 | ltned 11398 | . . . . 5
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → 𝑥 ≠ 𝐵) | 
| 29 | 28 | neneqd 2944 | . . . 4
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → ¬ 𝑥 = 𝐵) | 
| 30 | 29 | iffalsed 4535 | . . 3
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → if(𝑥 = 𝐵, 𝐿, (𝐹‘𝑥)) = (𝐹‘𝑥)) | 
| 31 | 21 | fveq2d 6909 | . . 3
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → (𝐹‘𝑥) = (𝐹‘𝐶)) | 
| 32 | 20, 30, 31 | 3eqtrd 2780 | . 2
⊢ ((𝜑 ∧ 𝑥 = 𝐶) → if(𝑥 = 𝐴, 𝑅, if(𝑥 = 𝐵, 𝐿, (𝐹‘𝑥))) = (𝐹‘𝐶)) | 
| 33 |  | ioossicc 13474 | . . 3
⊢ (𝐴(,)𝐵) ⊆ (𝐴[,]𝐵) | 
| 34 | 33, 5 | sselid 3980 | . 2
⊢ (𝜑 → 𝐶 ∈ (𝐴[,]𝐵)) | 
| 35 |  | cncfioobdlem.f | . . 3
⊢ (𝜑 → 𝐹:(𝐴(,)𝐵)⟶𝑉) | 
| 36 | 35, 5 | ffvelcdmd 7104 | . 2
⊢ (𝜑 → (𝐹‘𝐶) ∈ 𝑉) | 
| 37 | 2, 32, 34, 36 | fvmptd 7022 | 1
⊢ (𝜑 → (𝐺‘𝐶) = (𝐹‘𝐶)) |