Step |
Hyp |
Ref |
Expression |
1 |
|
salpreimalegt.x |
⊢ Ⅎ 𝑥 𝜑 |
2 |
|
salpreimalegt.a |
⊢ Ⅎ 𝑎 𝜑 |
3 |
|
salpreimalegt.s |
⊢ ( 𝜑 → 𝑆 ∈ SAlg ) |
4 |
|
salpreimalegt.u |
⊢ 𝐴 = ∪ 𝑆 |
5 |
|
salpreimalegt.b |
⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐵 ∈ ℝ* ) |
6 |
|
salpreimalegt.p |
⊢ ( ( 𝜑 ∧ 𝑎 ∈ ℝ ) → { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝑎 } ∈ 𝑆 ) |
7 |
|
salpreimalegt.c |
⊢ ( 𝜑 → 𝐶 ∈ ℝ ) |
8 |
4
|
eqcomi |
⊢ ∪ 𝑆 = 𝐴 |
9 |
8
|
a1i |
⊢ ( 𝜑 → ∪ 𝑆 = 𝐴 ) |
10 |
9
|
difeq1d |
⊢ ( 𝜑 → ( ∪ 𝑆 ∖ { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ) = ( 𝐴 ∖ { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ) ) |
11 |
7
|
rexrd |
⊢ ( 𝜑 → 𝐶 ∈ ℝ* ) |
12 |
1 5 11
|
preimalegt |
⊢ ( 𝜑 → ( 𝐴 ∖ { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ) = { 𝑥 ∈ 𝐴 ∣ 𝐶 < 𝐵 } ) |
13 |
10 12
|
eqtr2d |
⊢ ( 𝜑 → { 𝑥 ∈ 𝐴 ∣ 𝐶 < 𝐵 } = ( ∪ 𝑆 ∖ { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ) ) |
14 |
7
|
ancli |
⊢ ( 𝜑 → ( 𝜑 ∧ 𝐶 ∈ ℝ ) ) |
15 |
|
nfv |
⊢ Ⅎ 𝑎 𝐶 ∈ ℝ |
16 |
2 15
|
nfan |
⊢ Ⅎ 𝑎 ( 𝜑 ∧ 𝐶 ∈ ℝ ) |
17 |
|
nfv |
⊢ Ⅎ 𝑎 { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ∈ 𝑆 |
18 |
16 17
|
nfim |
⊢ Ⅎ 𝑎 ( ( 𝜑 ∧ 𝐶 ∈ ℝ ) → { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ∈ 𝑆 ) |
19 |
|
eleq1 |
⊢ ( 𝑎 = 𝐶 → ( 𝑎 ∈ ℝ ↔ 𝐶 ∈ ℝ ) ) |
20 |
19
|
anbi2d |
⊢ ( 𝑎 = 𝐶 → ( ( 𝜑 ∧ 𝑎 ∈ ℝ ) ↔ ( 𝜑 ∧ 𝐶 ∈ ℝ ) ) ) |
21 |
|
breq2 |
⊢ ( 𝑎 = 𝐶 → ( 𝐵 ≤ 𝑎 ↔ 𝐵 ≤ 𝐶 ) ) |
22 |
21
|
rabbidv |
⊢ ( 𝑎 = 𝐶 → { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝑎 } = { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ) |
23 |
22
|
eleq1d |
⊢ ( 𝑎 = 𝐶 → ( { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝑎 } ∈ 𝑆 ↔ { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ∈ 𝑆 ) ) |
24 |
20 23
|
imbi12d |
⊢ ( 𝑎 = 𝐶 → ( ( ( 𝜑 ∧ 𝑎 ∈ ℝ ) → { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝑎 } ∈ 𝑆 ) ↔ ( ( 𝜑 ∧ 𝐶 ∈ ℝ ) → { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ∈ 𝑆 ) ) ) |
25 |
18 24 6
|
vtoclg1f |
⊢ ( 𝐶 ∈ ℝ → ( ( 𝜑 ∧ 𝐶 ∈ ℝ ) → { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ∈ 𝑆 ) ) |
26 |
7 14 25
|
sylc |
⊢ ( 𝜑 → { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ∈ 𝑆 ) |
27 |
3 26
|
saldifcld |
⊢ ( 𝜑 → ( ∪ 𝑆 ∖ { 𝑥 ∈ 𝐴 ∣ 𝐵 ≤ 𝐶 } ) ∈ 𝑆 ) |
28 |
13 27
|
eqeltrd |
⊢ ( 𝜑 → { 𝑥 ∈ 𝐴 ∣ 𝐶 < 𝐵 } ∈ 𝑆 ) |