Proof of Theorem constrsqrtcl
| Step | Hyp | Ref
| Expression |
| 1 | | fveq2 6872 |
. . . . 5
⊢ (𝑋 = 0 → (√‘𝑋) =
(√‘0)) |
| 2 | | sqrt0 15247 |
. . . . 5
⊢
(√‘0) = 0 |
| 3 | 1, 2 | eqtrdi 2785 |
. . . 4
⊢ (𝑋 = 0 → (√‘𝑋) = 0) |
| 4 | | 0zd 12592 |
. . . . 5
⊢ (𝑋 = 0 → 0 ∈
ℤ) |
| 5 | 4 | zconstr 33714 |
. . . 4
⊢ (𝑋 = 0 → 0 ∈
Constr) |
| 6 | 3, 5 | eqeltrd 2833 |
. . 3
⊢ (𝑋 = 0 → (√‘𝑋) ∈
Constr) |
| 7 | 6 | adantl 481 |
. 2
⊢ ((𝜑 ∧ 𝑋 = 0) → (√‘𝑋) ∈
Constr) |
| 8 | | constrabscl.1 |
. . . . . . . . . 10
⊢ (𝜑 → 𝑋 ∈ Constr) |
| 9 | 8 | constrcn 33710 |
. . . . . . . . 9
⊢ (𝜑 → 𝑋 ∈ ℂ) |
| 10 | 9 | adantr 480 |
. . . . . . . 8
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → 𝑋 ∈
ℂ) |
| 11 | 10 | negnegd 11577 |
. . . . . . 7
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → --𝑋 = 𝑋) |
| 12 | 11 | fveq2d 6876 |
. . . . . 6
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) →
(√‘--𝑋) =
(√‘𝑋)) |
| 13 | | simpr 484 |
. . . . . . . 8
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → -𝑋 ∈
ℝ+) |
| 14 | 13 | rpred 13043 |
. . . . . . 7
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → -𝑋 ∈
ℝ) |
| 15 | 13 | rpge0d 13047 |
. . . . . . 7
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → 0 ≤
-𝑋) |
| 16 | 14, 15 | sqrtnegd 15427 |
. . . . . 6
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) →
(√‘--𝑋) = (i
· (√‘-𝑋))) |
| 17 | 12, 16 | eqtr3d 2771 |
. . . . 5
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) →
(√‘𝑋) = (i
· (√‘-𝑋))) |
| 18 | | iconstr 33716 |
. . . . . . 7
⊢ i ∈
Constr |
| 19 | 18 | a1i 11 |
. . . . . 6
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → i ∈
Constr) |
| 20 | 8 | adantr 480 |
. . . . . . . 8
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → 𝑋 ∈ Constr) |
| 21 | 20 | constrnegcl 33713 |
. . . . . . 7
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → -𝑋 ∈ Constr) |
| 22 | 21, 14, 15 | constrresqrtcl 33727 |
. . . . . 6
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) →
(√‘-𝑋) ∈
Constr) |
| 23 | 19, 22 | constrmulcl 33721 |
. . . . 5
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) → (i
· (√‘-𝑋)) ∈ Constr) |
| 24 | 17, 23 | eqeltrd 2833 |
. . . 4
⊢ ((𝜑 ∧ -𝑋 ∈ ℝ+) →
(√‘𝑋) ∈
Constr) |
| 25 | 24 | adantlr 715 |
. . 3
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ -𝑋 ∈ ℝ+) →
(√‘𝑋) ∈
Constr) |
| 26 | 9 | ad2antrr 726 |
. . . . . . . . 9
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) → 𝑋 ∈
ℂ) |
| 27 | 26 | abscld 15442 |
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(abs‘𝑋) ∈
ℝ) |
| 28 | 27 | recnd 11255 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(abs‘𝑋) ∈
ℂ) |
| 29 | 28 | sqrtcld 15443 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(√‘(abs‘𝑋)) ∈ ℂ) |
| 30 | 28, 26 | addcld 11246 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
((abs‘𝑋) + 𝑋) ∈
ℂ) |
| 31 | 30 | abscld 15442 |
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(abs‘((abs‘𝑋) +
𝑋)) ∈
ℝ) |
| 32 | 31 | recnd 11255 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(abs‘((abs‘𝑋) +
𝑋)) ∈
ℂ) |
| 33 | 9 | ad2antrr 726 |
. . . . . . . . . . . . 13
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → 𝑋 ∈ ℂ) |
| 34 | 9 | abscld 15442 |
. . . . . . . . . . . . . . . . . . . 20
⊢ (𝜑 → (abs‘𝑋) ∈
ℝ) |
| 35 | 34 | ad2antrr 726 |
. . . . . . . . . . . . . . . . . . 19
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → (abs‘𝑋) ∈
ℝ) |
| 36 | 35 | recnd 11255 |
. . . . . . . . . . . . . . . . . 18
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → (abs‘𝑋) ∈
ℂ) |
| 37 | | simpr 484 |
. . . . . . . . . . . . . . . . . 18
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → ((abs‘𝑋) + 𝑋) = 0) |
| 38 | | addeq0 11652 |
. . . . . . . . . . . . . . . . . . 19
⊢
(((abs‘𝑋)
∈ ℂ ∧ 𝑋
∈ ℂ) → (((abs‘𝑋) + 𝑋) = 0 ↔ (abs‘𝑋) = -𝑋)) |
| 39 | 38 | biimpa 476 |
. . . . . . . . . . . . . . . . . 18
⊢
((((abs‘𝑋)
∈ ℂ ∧ 𝑋
∈ ℂ) ∧ ((abs‘𝑋) + 𝑋) = 0) → (abs‘𝑋) = -𝑋) |
| 40 | 36, 33, 37, 39 | syl21anc 837 |
. . . . . . . . . . . . . . . . 17
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → (abs‘𝑋) = -𝑋) |
| 41 | 40, 35 | eqeltrrd 2834 |
. . . . . . . . . . . . . . . 16
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → -𝑋 ∈ ℝ) |
| 42 | 33, 41 | negrebd 11585 |
. . . . . . . . . . . . . . 15
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → 𝑋 ∈ ℝ) |
| 43 | | 0red 11230 |
. . . . . . . . . . . . . . . 16
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → 0 ∈
ℝ) |
| 44 | | simplr 768 |
. . . . . . . . . . . . . . . . 17
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → ¬ -𝑋 ∈
ℝ+) |
| 45 | | negelrp 13034 |
. . . . . . . . . . . . . . . . . . 19
⊢ (𝑋 ∈ ℝ → (-𝑋 ∈ ℝ+
↔ 𝑋 <
0)) |
| 46 | 45 | notbid 318 |
. . . . . . . . . . . . . . . . . 18
⊢ (𝑋 ∈ ℝ → (¬
-𝑋 ∈
ℝ+ ↔ ¬ 𝑋 < 0)) |
| 47 | 46 | biimpa 476 |
. . . . . . . . . . . . . . . . 17
⊢ ((𝑋 ∈ ℝ ∧ ¬
-𝑋 ∈
ℝ+) → ¬ 𝑋 < 0) |
| 48 | 42, 44, 47 | syl2anc 584 |
. . . . . . . . . . . . . . . 16
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → ¬ 𝑋 < 0) |
| 49 | 43, 42, 48 | nltled 11377 |
. . . . . . . . . . . . . . 15
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → 0 ≤ 𝑋) |
| 50 | 42, 49 | absidd 15428 |
. . . . . . . . . . . . . 14
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → (abs‘𝑋) = 𝑋) |
| 51 | 50, 40 | eqtr3d 2771 |
. . . . . . . . . . . . 13
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → 𝑋 = -𝑋) |
| 52 | 33, 51 | eqnegad 11955 |
. . . . . . . . . . . 12
⊢ (((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) ∧
((abs‘𝑋) + 𝑋) = 0) → 𝑋 = 0) |
| 53 | 52 | ex 412 |
. . . . . . . . . . 11
⊢ ((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) →
(((abs‘𝑋) + 𝑋) = 0 → 𝑋 = 0)) |
| 54 | 53 | necon3d 2952 |
. . . . . . . . . 10
⊢ ((𝜑 ∧ ¬ -𝑋 ∈ ℝ+) → (𝑋 ≠ 0 → ((abs‘𝑋) + 𝑋) ≠ 0)) |
| 55 | 54 | impancom 451 |
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑋 ≠ 0) → (¬ -𝑋 ∈ ℝ+ →
((abs‘𝑋) + 𝑋) ≠ 0)) |
| 56 | 55 | imp 406 |
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
((abs‘𝑋) + 𝑋) ≠ 0) |
| 57 | 30, 56 | absne0d 15453 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(abs‘((abs‘𝑋) +
𝑋)) ≠
0) |
| 58 | 30, 32, 57 | divcld 12009 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))) ∈ ℂ) |
| 59 | 29, 58 | mulcld 11247 |
. . . . 5
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋)))) ∈ ℂ) |
| 60 | | eqid 2734 |
. . . . . . . 8
⊢
((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋)))) = ((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋)))) |
| 61 | 60 | sqreulem 15365 |
. . . . . . 7
⊢ ((𝑋 ∈ ℂ ∧
((abs‘𝑋) + 𝑋) ≠ 0) →
((((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))↑2) = 𝑋 ∧ 0 ≤
(ℜ‘((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∧ (i ·
((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∉
ℝ+)) |
| 62 | 26, 56, 61 | syl2anc 584 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
((((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))↑2) = 𝑋 ∧ 0 ≤
(ℜ‘((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∧ (i ·
((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∉
ℝ+)) |
| 63 | 62 | simp1d 1142 |
. . . . 5
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))↑2) = 𝑋) |
| 64 | 62 | simp2d 1143 |
. . . . 5
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) → 0 ≤
(ℜ‘((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋)))))) |
| 65 | 62 | simp3d 1144 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) → (i
· ((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∉
ℝ+) |
| 66 | | df-nel 3036 |
. . . . . 6
⊢ ((i
· ((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∉ ℝ+ ↔
¬ (i · ((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∈
ℝ+) |
| 67 | 65, 66 | sylib 218 |
. . . . 5
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) → ¬ (i
· ((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))))) ∈
ℝ+) |
| 68 | 59, 26, 63, 64, 67 | eqsqrtd 15373 |
. . . 4
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋)))) = (√‘𝑋)) |
| 69 | 8 | ad2antrr 726 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) → 𝑋 ∈ Constr) |
| 70 | 69 | constrabscl 33728 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(abs‘𝑋) ∈
Constr) |
| 71 | 26 | absge0d 15450 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) → 0 ≤
(abs‘𝑋)) |
| 72 | 70, 27, 71 | constrresqrtcl 33727 |
. . . . 5
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(√‘(abs‘𝑋)) ∈ Constr) |
| 73 | 70, 69 | constraddcl 33712 |
. . . . . 6
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
((abs‘𝑋) + 𝑋) ∈
Constr) |
| 74 | 73, 56 | constrdircl 33715 |
. . . . 5
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋))) ∈ Constr) |
| 75 | 72, 74 | constrmulcl 33721 |
. . . 4
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
((√‘(abs‘𝑋)) · (((abs‘𝑋) + 𝑋) / (abs‘((abs‘𝑋) + 𝑋)))) ∈ Constr) |
| 76 | 68, 75 | eqeltrrd 2834 |
. . 3
⊢ (((𝜑 ∧ 𝑋 ≠ 0) ∧ ¬ -𝑋 ∈ ℝ+) →
(√‘𝑋) ∈
Constr) |
| 77 | 25, 76 | pm2.61dan 812 |
. 2
⊢ ((𝜑 ∧ 𝑋 ≠ 0) → (√‘𝑋) ∈
Constr) |
| 78 | 7, 77 | pm2.61dane 3018 |
1
⊢ (𝜑 → (√‘𝑋) ∈
Constr) |