Database
BASIC REAL AND COMPLEX ANALYSIS
Integrals
Lebesgue integration
Lesbesgue integral
itg2cnlem1
Next ⟩
itg2cnlem2
Metamath Proof Explorer
Ascii
Unicode
Theorem
itg2cnlem1
Description:
Lemma for
itgcn
.
(Contributed by
Mario Carneiro
, 30-Aug-2014)
Ref
Expression
Hypotheses
itg2cn.1
⊢
φ
→
F
:
ℝ
⟶
0
+∞
itg2cn.2
⊢
φ
→
F
∈
MblFn
itg2cn.3
⊢
φ
→
∫
2
F
∈
ℝ
Assertion
itg2cnlem1
⊢
φ
→
sup
ran
n
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
ℝ
*
<
=
∫
2
F
Proof
Step
Hyp
Ref
Expression
1
itg2cn.1
⊢
φ
→
F
:
ℝ
⟶
0
+∞
2
itg2cn.2
⊢
φ
→
F
∈
MblFn
3
itg2cn.3
⊢
φ
→
∫
2
F
∈
ℝ
4
fvex
⊢
F
x
∈
V
5
c0ex
⊢
0
∈
V
6
4
5
ifex
⊢
if
F
x
≤
n
F
x
0
∈
V
7
eqid
⊢
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
8
7
fvmpt2
⊢
x
∈
ℝ
∧
if
F
x
≤
n
F
x
0
∈
V
→
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
if
F
x
≤
n
F
x
0
9
6
8
mpan2
⊢
x
∈
ℝ
→
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
if
F
x
≤
n
F
x
0
10
9
mpteq2dv
⊢
x
∈
ℝ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
11
10
rneqd
⊢
x
∈
ℝ
→
ran
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
12
11
supeq1d
⊢
x
∈
ℝ
→
sup
ran
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
ℝ
<
=
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
13
12
mpteq2ia
⊢
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
ℝ
<
=
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
14
nfcv
⊢
Ⅎ
_
y
sup
ran
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
ℝ
<
15
nfcv
⊢
Ⅎ
_
x
ℕ
16
nfmpt1
⊢
Ⅎ
_
x
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
17
15
16
nfmpt
⊢
Ⅎ
_
x
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
18
nfcv
⊢
Ⅎ
_
x
m
19
17
18
nffv
⊢
Ⅎ
_
x
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
20
nfcv
⊢
Ⅎ
_
x
y
21
19
20
nffv
⊢
Ⅎ
_
x
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
22
15
21
nfmpt
⊢
Ⅎ
_
x
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
23
22
nfrn
⊢
Ⅎ
_
x
ran
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
24
nfcv
⊢
Ⅎ
_
x
ℝ
25
nfcv
⊢
Ⅎ
_
x
<
26
23
24
25
nfsup
⊢
Ⅎ
_
x
sup
ran
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
ℝ
<
27
fveq2
⊢
x
=
y
→
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
y
28
27
mpteq2dv
⊢
x
=
y
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
y
29
breq2
⊢
n
=
m
→
F
x
≤
n
↔
F
x
≤
m
30
29
ifbid
⊢
n
=
m
→
if
F
x
≤
n
F
x
0
=
if
F
x
≤
m
F
x
0
31
30
mpteq2dv
⊢
n
=
m
→
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
32
31
fveq1d
⊢
n
=
m
→
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
y
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
33
32
cbvmptv
⊢
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
y
=
m
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
34
eqid
⊢
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
35
reex
⊢
ℝ
∈
V
36
35
mptex
⊢
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
∈
V
37
31
34
36
fvmpt
⊢
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
38
37
fveq1d
⊢
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
39
38
mpteq2ia
⊢
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
=
m
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
40
33
39
eqtr4i
⊢
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
y
=
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
41
28
40
eqtrdi
⊢
x
=
y
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
42
41
rneqd
⊢
x
=
y
→
ran
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
=
ran
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
43
42
supeq1d
⊢
x
=
y
→
sup
ran
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
ℝ
<
=
sup
ran
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
ℝ
<
44
14
26
43
cbvmpt
⊢
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
x
ℝ
<
=
y
∈
ℝ
⟼
sup
ran
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
ℝ
<
45
13
44
eqtr3i
⊢
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
=
y
∈
ℝ
⟼
sup
ran
m
∈
ℕ
⟼
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
ℝ
<
46
fveq2
⊢
x
=
y
→
F
x
=
F
y
47
46
breq1d
⊢
x
=
y
→
F
x
≤
m
↔
F
y
≤
m
48
47
46
ifbieq1d
⊢
x
=
y
→
if
F
x
≤
m
F
x
0
=
if
F
y
≤
m
F
y
0
49
48
cbvmptv
⊢
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
=
y
∈
ℝ
⟼
if
F
y
≤
m
F
y
0
50
37
adantl
⊢
φ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
51
nnre
⊢
m
∈
ℕ
→
m
∈
ℝ
52
51
ad2antlr
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
m
∈
ℝ
53
52
rexrd
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
m
∈
ℝ
*
54
elioopnf
⊢
m
∈
ℝ
*
→
F
y
∈
m
+∞
↔
F
y
∈
ℝ
∧
m
<
F
y
55
53
54
syl
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
F
y
∈
m
+∞
↔
F
y
∈
ℝ
∧
m
<
F
y
56
simpr
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
y
∈
ℝ
57
1
ffnd
⊢
φ
→
F
Fn
ℝ
58
57
ad2antrr
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
F
Fn
ℝ
59
elpreima
⊢
F
Fn
ℝ
→
y
∈
F
-1
m
+∞
↔
y
∈
ℝ
∧
F
y
∈
m
+∞
60
58
59
syl
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
y
∈
F
-1
m
+∞
↔
y
∈
ℝ
∧
F
y
∈
m
+∞
61
56
60
mpbirand
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
y
∈
F
-1
m
+∞
↔
F
y
∈
m
+∞
62
rge0ssre
⊢
0
+∞
⊆
ℝ
63
fss
⊢
F
:
ℝ
⟶
0
+∞
∧
0
+∞
⊆
ℝ
→
F
:
ℝ
⟶
ℝ
64
1
62
63
sylancl
⊢
φ
→
F
:
ℝ
⟶
ℝ
65
64
adantr
⊢
φ
∧
m
∈
ℕ
→
F
:
ℝ
⟶
ℝ
66
65
ffvelcdmda
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
F
y
∈
ℝ
67
66
biantrurd
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
m
<
F
y
↔
F
y
∈
ℝ
∧
m
<
F
y
68
55
61
67
3bitr4d
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
y
∈
F
-1
m
+∞
↔
m
<
F
y
69
68
notbid
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
¬
y
∈
F
-1
m
+∞
↔
¬
m
<
F
y
70
eldif
⊢
y
∈
ℝ
∖
F
-1
m
+∞
↔
y
∈
ℝ
∧
¬
y
∈
F
-1
m
+∞
71
70
baib
⊢
y
∈
ℝ
→
y
∈
ℝ
∖
F
-1
m
+∞
↔
¬
y
∈
F
-1
m
+∞
72
71
adantl
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
y
∈
ℝ
∖
F
-1
m
+∞
↔
¬
y
∈
F
-1
m
+∞
73
66
52
lenltd
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
F
y
≤
m
↔
¬
m
<
F
y
74
69
72
73
3bitr4d
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
y
∈
ℝ
∖
F
-1
m
+∞
↔
F
y
≤
m
75
74
ifbid
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
=
if
F
y
≤
m
F
y
0
76
75
mpteq2dva
⊢
φ
∧
m
∈
ℕ
→
y
∈
ℝ
⟼
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
=
y
∈
ℝ
⟼
if
F
y
≤
m
F
y
0
77
49
50
76
3eqtr4a
⊢
φ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
=
y
∈
ℝ
⟼
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
78
difss
⊢
ℝ
∖
F
-1
m
+∞
⊆
ℝ
79
78
a1i
⊢
φ
∧
m
∈
ℕ
→
ℝ
∖
F
-1
m
+∞
⊆
ℝ
80
rembl
⊢
ℝ
∈
dom
vol
81
80
a1i
⊢
φ
∧
m
∈
ℕ
→
ℝ
∈
dom
vol
82
fvex
⊢
F
y
∈
V
83
82
5
ifex
⊢
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
∈
V
84
83
a1i
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
∖
F
-1
m
+∞
→
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
∈
V
85
eldifn
⊢
y
∈
ℝ
∖
ℝ
∖
F
-1
m
+∞
→
¬
y
∈
ℝ
∖
F
-1
m
+∞
86
85
adantl
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
∖
ℝ
∖
F
-1
m
+∞
→
¬
y
∈
ℝ
∖
F
-1
m
+∞
87
86
iffalsed
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
∖
ℝ
∖
F
-1
m
+∞
→
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
=
0
88
iftrue
⊢
y
∈
ℝ
∖
F
-1
m
+∞
→
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
=
F
y
89
88
mpteq2ia
⊢
y
∈
ℝ
∖
F
-1
m
+∞
⟼
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
=
y
∈
ℝ
∖
F
-1
m
+∞
⟼
F
y
90
resmpt
⊢
ℝ
∖
F
-1
m
+∞
⊆
ℝ
→
y
∈
ℝ
⟼
F
y
↾
ℝ
∖
F
-1
m
+∞
=
y
∈
ℝ
∖
F
-1
m
+∞
⟼
F
y
91
78
90
ax-mp
⊢
y
∈
ℝ
⟼
F
y
↾
ℝ
∖
F
-1
m
+∞
=
y
∈
ℝ
∖
F
-1
m
+∞
⟼
F
y
92
89
91
eqtr4i
⊢
y
∈
ℝ
∖
F
-1
m
+∞
⟼
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
=
y
∈
ℝ
⟼
F
y
↾
ℝ
∖
F
-1
m
+∞
93
1
feqmptd
⊢
φ
→
F
=
y
∈
ℝ
⟼
F
y
94
93
2
eqeltrrd
⊢
φ
→
y
∈
ℝ
⟼
F
y
∈
MblFn
95
mbfima
⊢
F
∈
MblFn
∧
F
:
ℝ
⟶
ℝ
→
F
-1
m
+∞
∈
dom
vol
96
2
64
95
syl2anc
⊢
φ
→
F
-1
m
+∞
∈
dom
vol
97
cmmbl
⊢
F
-1
m
+∞
∈
dom
vol
→
ℝ
∖
F
-1
m
+∞
∈
dom
vol
98
96
97
syl
⊢
φ
→
ℝ
∖
F
-1
m
+∞
∈
dom
vol
99
mbfres
⊢
y
∈
ℝ
⟼
F
y
∈
MblFn
∧
ℝ
∖
F
-1
m
+∞
∈
dom
vol
→
y
∈
ℝ
⟼
F
y
↾
ℝ
∖
F
-1
m
+∞
∈
MblFn
100
94
98
99
syl2anc
⊢
φ
→
y
∈
ℝ
⟼
F
y
↾
ℝ
∖
F
-1
m
+∞
∈
MblFn
101
92
100
eqeltrid
⊢
φ
→
y
∈
ℝ
∖
F
-1
m
+∞
⟼
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
∈
MblFn
102
101
adantr
⊢
φ
∧
m
∈
ℕ
→
y
∈
ℝ
∖
F
-1
m
+∞
⟼
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
∈
MblFn
103
79
81
84
87
102
mbfss
⊢
φ
∧
m
∈
ℕ
→
y
∈
ℝ
⟼
if
y
∈
ℝ
∖
F
-1
m
+∞
F
y
0
∈
MblFn
104
77
103
eqeltrd
⊢
φ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
∈
MblFn
105
1
ffvelcdmda
⊢
φ
∧
x
∈
ℝ
→
F
x
∈
0
+∞
106
0e0icopnf
⊢
0
∈
0
+∞
107
ifcl
⊢
F
x
∈
0
+∞
∧
0
∈
0
+∞
→
if
F
x
≤
m
F
x
0
∈
0
+∞
108
105
106
107
sylancl
⊢
φ
∧
x
∈
ℝ
→
if
F
x
≤
m
F
x
0
∈
0
+∞
109
108
adantlr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
→
if
F
x
≤
m
F
x
0
∈
0
+∞
110
50
109
fmpt3d
⊢
φ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
:
ℝ
⟶
0
+∞
111
elrege0
⊢
F
x
∈
0
+∞
↔
F
x
∈
ℝ
∧
0
≤
F
x
112
105
111
sylib
⊢
φ
∧
x
∈
ℝ
→
F
x
∈
ℝ
∧
0
≤
F
x
113
112
simpld
⊢
φ
∧
x
∈
ℝ
→
F
x
∈
ℝ
114
113
adantlr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
→
F
x
∈
ℝ
115
114
adantr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
F
x
∈
ℝ
116
115
leidd
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
F
x
≤
F
x
117
iftrue
⊢
F
x
≤
m
→
if
F
x
≤
m
F
x
0
=
F
x
118
117
adantl
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
if
F
x
≤
m
F
x
0
=
F
x
119
51
ad3antlr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
m
∈
ℝ
120
peano2re
⊢
m
∈
ℝ
→
m
+
1
∈
ℝ
121
119
120
syl
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
m
+
1
∈
ℝ
122
simpr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
F
x
≤
m
123
119
lep1d
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
m
≤
m
+
1
124
115
119
121
122
123
letrd
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
F
x
≤
m
+
1
125
124
iftrued
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
if
F
x
≤
m
+
1
F
x
0
=
F
x
126
116
118
125
3brtr4d
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
F
x
≤
m
→
if
F
x
≤
m
F
x
0
≤
if
F
x
≤
m
+
1
F
x
0
127
iffalse
⊢
¬
F
x
≤
m
→
if
F
x
≤
m
F
x
0
=
0
128
127
adantl
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
¬
F
x
≤
m
→
if
F
x
≤
m
F
x
0
=
0
129
112
simprd
⊢
φ
∧
x
∈
ℝ
→
0
≤
F
x
130
0le0
⊢
0
≤
0
131
breq2
⊢
F
x
=
if
F
x
≤
m
+
1
F
x
0
→
0
≤
F
x
↔
0
≤
if
F
x
≤
m
+
1
F
x
0
132
breq2
⊢
0
=
if
F
x
≤
m
+
1
F
x
0
→
0
≤
0
↔
0
≤
if
F
x
≤
m
+
1
F
x
0
133
131
132
ifboth
⊢
0
≤
F
x
∧
0
≤
0
→
0
≤
if
F
x
≤
m
+
1
F
x
0
134
129
130
133
sylancl
⊢
φ
∧
x
∈
ℝ
→
0
≤
if
F
x
≤
m
+
1
F
x
0
135
134
adantlr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
→
0
≤
if
F
x
≤
m
+
1
F
x
0
136
135
adantr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
¬
F
x
≤
m
→
0
≤
if
F
x
≤
m
+
1
F
x
0
137
128
136
eqbrtrd
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
∧
¬
F
x
≤
m
→
if
F
x
≤
m
F
x
0
≤
if
F
x
≤
m
+
1
F
x
0
138
126
137
pm2.61dan
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
→
if
F
x
≤
m
F
x
0
≤
if
F
x
≤
m
+
1
F
x
0
139
138
ralrimiva
⊢
φ
∧
m
∈
ℕ
→
∀
x
∈
ℝ
if
F
x
≤
m
F
x
0
≤
if
F
x
≤
m
+
1
F
x
0
140
4
5
ifex
⊢
if
F
x
≤
m
+
1
F
x
0
∈
V
141
140
a1i
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
→
if
F
x
≤
m
+
1
F
x
0
∈
V
142
eqidd
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
143
eqidd
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
=
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
144
81
109
141
142
143
ofrfval2
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
≤
f
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
↔
∀
x
∈
ℝ
if
F
x
≤
m
F
x
0
≤
if
F
x
≤
m
+
1
F
x
0
145
139
144
mpbird
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
≤
f
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
146
peano2nn
⊢
m
∈
ℕ
→
m
+
1
∈
ℕ
147
146
adantl
⊢
φ
∧
m
∈
ℕ
→
m
+
1
∈
ℕ
148
breq2
⊢
n
=
m
+
1
→
F
x
≤
n
↔
F
x
≤
m
+
1
149
148
ifbid
⊢
n
=
m
+
1
→
if
F
x
≤
n
F
x
0
=
if
F
x
≤
m
+
1
F
x
0
150
149
mpteq2dv
⊢
n
=
m
+
1
→
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
151
35
mptex
⊢
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
∈
V
152
150
34
151
fvmpt
⊢
m
+
1
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
+
1
=
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
153
147
152
syl
⊢
φ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
+
1
=
x
∈
ℝ
⟼
if
F
x
≤
m
+
1
F
x
0
154
145
50
153
3brtr4d
⊢
φ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
≤
f
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
+
1
155
64
ffvelcdmda
⊢
φ
∧
y
∈
ℝ
→
F
y
∈
ℝ
156
37
adantl
⊢
φ
∧
y
∈
ℝ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
157
156
fveq1d
⊢
φ
∧
y
∈
ℝ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
158
113
leidd
⊢
φ
∧
x
∈
ℝ
→
F
x
≤
F
x
159
breq1
⊢
F
x
=
if
F
x
≤
m
F
x
0
→
F
x
≤
F
x
↔
if
F
x
≤
m
F
x
0
≤
F
x
160
breq1
⊢
0
=
if
F
x
≤
m
F
x
0
→
0
≤
F
x
↔
if
F
x
≤
m
F
x
0
≤
F
x
161
159
160
ifboth
⊢
F
x
≤
F
x
∧
0
≤
F
x
→
if
F
x
≤
m
F
x
0
≤
F
x
162
158
129
161
syl2anc
⊢
φ
∧
x
∈
ℝ
→
if
F
x
≤
m
F
x
0
≤
F
x
163
162
adantlr
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
→
if
F
x
≤
m
F
x
0
≤
F
x
164
163
ralrimiva
⊢
φ
∧
m
∈
ℕ
→
∀
x
∈
ℝ
if
F
x
≤
m
F
x
0
≤
F
x
165
35
a1i
⊢
φ
∧
m
∈
ℕ
→
ℝ
∈
V
166
4
5
ifex
⊢
if
F
x
≤
m
F
x
0
∈
V
167
166
a1i
⊢
φ
∧
m
∈
ℕ
∧
x
∈
ℝ
→
if
F
x
≤
m
F
x
0
∈
V
168
1
feqmptd
⊢
φ
→
F
=
x
∈
ℝ
⟼
F
x
169
168
adantr
⊢
φ
∧
m
∈
ℕ
→
F
=
x
∈
ℝ
⟼
F
x
170
165
167
114
142
169
ofrfval2
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
≤
f
F
↔
∀
x
∈
ℝ
if
F
x
≤
m
F
x
0
≤
F
x
171
164
170
mpbird
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
≤
f
F
172
167
fmpttd
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
:
ℝ
⟶
V
173
172
ffnd
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
Fn
ℝ
174
57
adantr
⊢
φ
∧
m
∈
ℕ
→
F
Fn
ℝ
175
inidm
⊢
ℝ
∩
ℝ
=
ℝ
176
eqidd
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
=
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
177
eqidd
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
F
y
=
F
y
178
173
174
165
165
175
176
177
ofrfval
⊢
φ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
≤
f
F
↔
∀
y
∈
ℝ
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
≤
F
y
179
171
178
mpbid
⊢
φ
∧
m
∈
ℕ
→
∀
y
∈
ℝ
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
≤
F
y
180
179
r19.21bi
⊢
φ
∧
m
∈
ℕ
∧
y
∈
ℝ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
≤
F
y
181
180
an32s
⊢
φ
∧
y
∈
ℝ
∧
m
∈
ℕ
→
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
y
≤
F
y
182
157
181
eqbrtrd
⊢
φ
∧
y
∈
ℝ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
≤
F
y
183
182
ralrimiva
⊢
φ
∧
y
∈
ℝ
→
∀
m
∈
ℕ
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
≤
F
y
184
brralrspcev
⊢
F
y
∈
ℝ
∧
∀
m
∈
ℕ
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
≤
F
y
→
∃
z
∈
ℝ
∀
m
∈
ℕ
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
≤
z
185
155
183
184
syl2anc
⊢
φ
∧
y
∈
ℝ
→
∃
z
∈
ℝ
∀
m
∈
ℕ
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
y
≤
z
186
31
fveq2d
⊢
n
=
m
→
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
∫
2
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
187
186
cbvmptv
⊢
n
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
m
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
188
37
fveq2d
⊢
m
∈
ℕ
→
∫
2
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
=
∫
2
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
189
188
mpteq2ia
⊢
m
∈
ℕ
⟼
∫
2
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
=
m
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
m
F
x
0
190
187
189
eqtr4i
⊢
n
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
m
∈
ℕ
⟼
∫
2
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
191
190
rneqi
⊢
ran
n
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
=
ran
m
∈
ℕ
⟼
∫
2
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
192
191
supeq1i
⊢
sup
ran
n
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
ℝ
*
<
=
sup
ran
m
∈
ℕ
⟼
∫
2
n
∈
ℕ
⟼
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
m
ℝ
*
<
193
45
104
110
154
185
192
itg2mono
⊢
φ
→
∫
2
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
=
sup
ran
n
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
ℝ
*
<
194
eqid
⊢
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
=
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
195
30
194
166
fvmpt
⊢
m
∈
ℕ
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
=
if
F
x
≤
m
F
x
0
196
195
adantl
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
=
if
F
x
≤
m
F
x
0
197
162
adantr
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
→
if
F
x
≤
m
F
x
0
≤
F
x
198
196
197
eqbrtrd
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
≤
F
x
199
198
ralrimiva
⊢
φ
∧
x
∈
ℝ
→
∀
m
∈
ℕ
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
≤
F
x
200
6
a1i
⊢
φ
∧
x
∈
ℝ
∧
n
∈
ℕ
→
if
F
x
≤
n
F
x
0
∈
V
201
200
fmpttd
⊢
φ
∧
x
∈
ℝ
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
:
ℕ
⟶
V
202
201
ffnd
⊢
φ
∧
x
∈
ℝ
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
Fn
ℕ
203
breq1
⊢
w
=
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
→
w
≤
F
x
↔
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
≤
F
x
204
203
ralrn
⊢
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
Fn
ℕ
→
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
F
x
↔
∀
m
∈
ℕ
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
≤
F
x
205
202
204
syl
⊢
φ
∧
x
∈
ℝ
→
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
F
x
↔
∀
m
∈
ℕ
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
≤
F
x
206
199
205
mpbird
⊢
φ
∧
x
∈
ℝ
→
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
F
x
207
113
adantr
⊢
φ
∧
x
∈
ℝ
∧
n
∈
ℕ
→
F
x
∈
ℝ
208
0re
⊢
0
∈
ℝ
209
ifcl
⊢
F
x
∈
ℝ
∧
0
∈
ℝ
→
if
F
x
≤
n
F
x
0
∈
ℝ
210
207
208
209
sylancl
⊢
φ
∧
x
∈
ℝ
∧
n
∈
ℕ
→
if
F
x
≤
n
F
x
0
∈
ℝ
211
210
fmpttd
⊢
φ
∧
x
∈
ℝ
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
:
ℕ
⟶
ℝ
212
211
frnd
⊢
φ
∧
x
∈
ℝ
→
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
⊆
ℝ
213
1nn
⊢
1
∈
ℕ
214
194
210
dmmptd
⊢
φ
∧
x
∈
ℝ
→
dom
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
=
ℕ
215
213
214
eleqtrrid
⊢
φ
∧
x
∈
ℝ
→
1
∈
dom
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
216
n0i
⊢
1
∈
dom
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
→
¬
dom
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
=
∅
217
dm0rn0
⊢
dom
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
=
∅
↔
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
=
∅
218
217
necon3bbii
⊢
¬
dom
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
=
∅
↔
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
≠
∅
219
216
218
sylib
⊢
1
∈
dom
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
→
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
≠
∅
220
215
219
syl
⊢
φ
∧
x
∈
ℝ
→
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
≠
∅
221
brralrspcev
⊢
F
x
∈
ℝ
∧
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
F
x
→
∃
z
∈
ℝ
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
z
222
113
206
221
syl2anc
⊢
φ
∧
x
∈
ℝ
→
∃
z
∈
ℝ
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
z
223
suprleub
⊢
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
⊆
ℝ
∧
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
≠
∅
∧
∃
z
∈
ℝ
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
z
∧
F
x
∈
ℝ
→
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
≤
F
x
↔
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
F
x
224
212
220
222
113
223
syl31anc
⊢
φ
∧
x
∈
ℝ
→
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
≤
F
x
↔
∀
w
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
w
≤
F
x
225
206
224
mpbird
⊢
φ
∧
x
∈
ℝ
→
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
≤
F
x
226
arch
⊢
F
x
∈
ℝ
→
∃
m
∈
ℕ
F
x
<
m
227
113
226
syl
⊢
φ
∧
x
∈
ℝ
→
∃
m
∈
ℕ
F
x
<
m
228
195
ad2antrl
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
=
if
F
x
≤
m
F
x
0
229
ltle
⊢
F
x
∈
ℝ
∧
m
∈
ℝ
→
F
x
<
m
→
F
x
≤
m
230
113
51
229
syl2an
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
→
F
x
<
m
→
F
x
≤
m
231
230
impr
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
F
x
≤
m
232
231
iftrued
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
if
F
x
≤
m
F
x
0
=
F
x
233
228
232
eqtrd
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
=
F
x
234
202
adantr
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
Fn
ℕ
235
simprl
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
m
∈
ℕ
236
fnfvelrn
⊢
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
Fn
ℕ
∧
m
∈
ℕ
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
237
234
235
236
syl2anc
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
m
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
238
233
237
eqeltrrd
⊢
φ
∧
x
∈
ℝ
∧
m
∈
ℕ
∧
F
x
<
m
→
F
x
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
239
227
238
rexlimddv
⊢
φ
∧
x
∈
ℝ
→
F
x
∈
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
240
212
220
222
239
suprubd
⊢
φ
∧
x
∈
ℝ
→
F
x
≤
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
241
212
220
222
suprcld
⊢
φ
∧
x
∈
ℝ
→
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
∈
ℝ
242
241
113
letri3d
⊢
φ
∧
x
∈
ℝ
→
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
=
F
x
↔
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
≤
F
x
∧
F
x
≤
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
243
225
240
242
mpbir2and
⊢
φ
∧
x
∈
ℝ
→
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
=
F
x
244
243
mpteq2dva
⊢
φ
→
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
=
x
∈
ℝ
⟼
F
x
245
244
168
eqtr4d
⊢
φ
→
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
=
F
246
245
fveq2d
⊢
φ
→
∫
2
x
∈
ℝ
⟼
sup
ran
n
∈
ℕ
⟼
if
F
x
≤
n
F
x
0
ℝ
<
=
∫
2
F
247
193
246
eqtr3d
⊢
φ
→
sup
ran
n
∈
ℕ
⟼
∫
2
x
∈
ℝ
⟼
if
F
x
≤
n
F
x
0
ℝ
*
<
=
∫
2
F