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SUPPLEMENTARY MATERIAL (USERS' MATHBOXES)
Mathbox for Alexander van der Vekens
Elementary geometry (extension)
Spheres and lines in real Euclidean spaces
itsclc0yqsollem1
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itsclc0yqsollem2
Metamath Proof Explorer
Ascii
Unicode
Theorem
itsclc0yqsollem1
Description:
Lemma 1 for
itsclc0yqsol
.
(Contributed by
AV
, 6-Feb-2023)
Ref
Expression
Hypotheses
itscnhlc0yqe.q
⊢
Q
=
A
2
+
B
2
itscnhlc0yqe.t
⊢
T
=
−
2
B
C
itscnhlc0yqe.u
⊢
U
=
C
2
−
A
2
R
2
itsclc0yqsollem1.d
⊢
D
=
R
2
Q
−
C
2
Assertion
itsclc0yqsollem1
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
T
2
−
4
Q
U
=
4
A
2
D
Proof
Step
Hyp
Ref
Expression
1
itscnhlc0yqe.q
⊢
Q
=
A
2
+
B
2
2
itscnhlc0yqe.t
⊢
T
=
−
2
B
C
3
itscnhlc0yqe.u
⊢
U
=
C
2
−
A
2
R
2
4
itsclc0yqsollem1.d
⊢
D
=
R
2
Q
−
C
2
5
2
oveq1i
⊢
T
2
=
−
2
B
C
2
6
2cnd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
2
∈
ℂ
7
simpl2
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
∈
ℂ
8
simpl3
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
C
∈
ℂ
9
7
8
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
C
∈
ℂ
10
6
9
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
2
B
C
∈
ℂ
11
sqneg
⊢
2
B
C
∈
ℂ
→
−
2
B
C
2
=
2
B
C
2
12
10
11
syl
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
−
2
B
C
2
=
2
B
C
2
13
6
9
sqmuld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
2
B
C
2
=
2
2
B
C
2
14
sq2
⊢
2
2
=
4
15
14
a1i
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
2
2
=
4
16
7
8
sqmuld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
C
2
=
B
2
C
2
17
15
16
oveq12d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
2
2
B
C
2
=
4
B
2
C
2
18
12
13
17
3eqtrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
−
2
B
C
2
=
4
B
2
C
2
19
5
18
eqtrid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
T
2
=
4
B
2
C
2
20
1
3
oveq12i
⊢
Q
U
=
A
2
+
B
2
C
2
−
A
2
R
2
21
simpl1
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
∈
ℂ
22
21
sqcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
∈
ℂ
23
7
sqcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
∈
ℂ
24
22
23
addcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
∈
ℂ
25
8
sqcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
C
2
∈
ℂ
26
simpr
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
∈
ℂ
27
26
sqcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
2
∈
ℂ
28
22
27
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
R
2
∈
ℂ
29
24
25
28
subdid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
C
2
−
A
2
R
2
=
A
2
+
B
2
C
2
−
A
2
+
B
2
A
2
R
2
30
22
23
25
adddird
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
C
2
=
A
2
C
2
+
B
2
C
2
31
22
23
28
adddird
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
A
2
R
2
=
A
2
A
2
R
2
+
B
2
A
2
R
2
32
30
31
oveq12d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
C
2
−
A
2
+
B
2
A
2
R
2
=
A
2
C
2
+
B
2
C
2
-
A
2
A
2
R
2
+
B
2
A
2
R
2
33
23
25
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
∈
ℂ
34
22
25
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
C
2
∈
ℂ
35
22
28
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
∈
ℂ
36
23
27
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
R
2
∈
ℂ
37
22
36
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
B
2
R
2
∈
ℂ
38
35
37
addcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
A
2
B
2
R
2
∈
ℂ
39
34
33
addcomd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
C
2
+
B
2
C
2
=
B
2
C
2
+
A
2
C
2
40
23
22
27
mul12d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
A
2
R
2
=
A
2
B
2
R
2
41
40
oveq2d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
B
2
A
2
R
2
=
A
2
A
2
R
2
+
A
2
B
2
R
2
42
39
41
oveq12d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
C
2
+
B
2
C
2
-
A
2
A
2
R
2
+
B
2
A
2
R
2
=
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
43
33
34
38
42
assraddsubd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
C
2
+
B
2
C
2
-
A
2
A
2
R
2
+
B
2
A
2
R
2
=
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
44
29
32
43
3eqtrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
C
2
−
A
2
R
2
=
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
45
20
44
eqtrid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
Q
U
=
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
46
45
oveq2d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
4
Q
U
=
4
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
47
19
46
oveq12d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
T
2
−
4
Q
U
=
4
B
2
C
2
−
4
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
48
4cn
⊢
4
∈
ℂ
49
48
a1i
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
4
∈
ℂ
50
simp1
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
→
A
∈
ℂ
51
50
sqcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
→
A
2
∈
ℂ
52
51
adantr
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
∈
ℂ
53
1
24
eqeltrid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
Q
∈
ℂ
54
27
53
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
2
Q
∈
ℂ
55
54
25
subcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
2
Q
−
C
2
∈
ℂ
56
4
55
eqeltrid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
D
∈
ℂ
57
49
52
56
mulassd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
4
A
2
D
=
4
A
2
D
58
34
38
subcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
C
2
−
A
2
A
2
R
2
+
A
2
B
2
R
2
∈
ℂ
59
33
33
58
subsub4d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
-
B
2
C
2
-
A
2
C
2
−
A
2
A
2
R
2
+
A
2
B
2
R
2
=
B
2
C
2
−
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
60
33
subidd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
−
B
2
C
2
=
0
61
60
oveq1d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
-
B
2
C
2
-
A
2
C
2
−
A
2
A
2
R
2
+
A
2
B
2
R
2
=
0
−
A
2
C
2
−
A
2
A
2
R
2
+
A
2
B
2
R
2
62
0cnd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
0
∈
ℂ
63
62
34
38
subsub2d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
0
−
A
2
C
2
−
A
2
A
2
R
2
+
A
2
B
2
R
2
=
0
+
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
64
38
34
subcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
∈
ℂ
65
64
addlidd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
0
+
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
=
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
66
61
63
65
3eqtrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
-
B
2
C
2
-
A
2
C
2
−
A
2
A
2
R
2
+
A
2
B
2
R
2
=
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
67
59
66
eqtr3d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
−
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
=
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
68
22
28
36
adddid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
B
2
R
2
=
A
2
A
2
R
2
+
A
2
B
2
R
2
69
22
23
27
adddird
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
R
2
=
A
2
R
2
+
B
2
R
2
70
69
eqcomd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
R
2
+
B
2
R
2
=
A
2
+
B
2
R
2
71
70
oveq2d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
B
2
R
2
=
A
2
A
2
+
B
2
R
2
72
68
71
eqtr3d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
A
2
B
2
R
2
=
A
2
A
2
+
B
2
R
2
73
72
oveq1d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
=
A
2
A
2
+
B
2
R
2
−
A
2
C
2
74
24
27
mulcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
R
2
∈
ℂ
75
22
74
25
subdid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
+
B
2
R
2
−
C
2
=
A
2
A
2
+
B
2
R
2
−
A
2
C
2
76
73
75
eqtr4d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
R
2
+
A
2
B
2
R
2
-
A
2
C
2
=
A
2
A
2
+
B
2
R
2
−
C
2
77
1
a1i
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
Q
=
A
2
+
B
2
78
77
oveq2d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
2
Q
=
R
2
A
2
+
B
2
79
27
24
mulcomd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
2
A
2
+
B
2
=
A
2
+
B
2
R
2
80
78
79
eqtrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
2
Q
=
A
2
+
B
2
R
2
81
80
oveq1d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
R
2
Q
−
C
2
=
A
2
+
B
2
R
2
−
C
2
82
4
81
eqtrid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
D
=
A
2
+
B
2
R
2
−
C
2
83
82
eqcomd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
+
B
2
R
2
−
C
2
=
D
84
83
oveq2d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
A
2
A
2
+
B
2
R
2
−
C
2
=
A
2
D
85
67
76
84
3eqtrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
−
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
=
A
2
D
86
85
oveq2d
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
4
B
2
C
2
−
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
=
4
A
2
D
87
33
58
addcld
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
∈
ℂ
88
49
33
87
subdid
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
4
B
2
C
2
−
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
=
4
B
2
C
2
−
4
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
89
57
86
88
3eqtr2rd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
4
B
2
C
2
−
4
B
2
C
2
+
A
2
C
2
-
A
2
A
2
R
2
+
A
2
B
2
R
2
=
4
A
2
D
90
47
89
eqtrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
R
∈
ℂ
→
T
2
−
4
Q
U
=
4
A
2
D