| Step |
Hyp |
Ref |
Expression |
| 1 |
|
diam.m |
⊢ ∧ = ( meet ‘ 𝐾 ) |
| 2 |
|
diam.h |
⊢ 𝐻 = ( LHyp ‘ 𝐾 ) |
| 3 |
|
diam.i |
⊢ 𝐼 = ( ( DIsoA ‘ 𝐾 ) ‘ 𝑊 ) |
| 4 |
|
simpl |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ) |
| 5 |
2 3
|
diacnvclN |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ 𝑋 ∈ ran 𝐼 ) → ( ◡ 𝐼 ‘ 𝑋 ) ∈ dom 𝐼 ) |
| 6 |
5
|
adantrr |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( ◡ 𝐼 ‘ 𝑋 ) ∈ dom 𝐼 ) |
| 7 |
2 3
|
diacnvclN |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ 𝑌 ∈ ran 𝐼 ) → ( ◡ 𝐼 ‘ 𝑌 ) ∈ dom 𝐼 ) |
| 8 |
7
|
adantrl |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( ◡ 𝐼 ‘ 𝑌 ) ∈ dom 𝐼 ) |
| 9 |
1 2 3
|
diameetN |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( ( ◡ 𝐼 ‘ 𝑋 ) ∈ dom 𝐼 ∧ ( ◡ 𝐼 ‘ 𝑌 ) ∈ dom 𝐼 ) ) → ( 𝐼 ‘ ( ( ◡ 𝐼 ‘ 𝑋 ) ∧ ( ◡ 𝐼 ‘ 𝑌 ) ) ) = ( ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑋 ) ) ∩ ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑌 ) ) ) ) |
| 10 |
4 6 8 9
|
syl12anc |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( 𝐼 ‘ ( ( ◡ 𝐼 ‘ 𝑋 ) ∧ ( ◡ 𝐼 ‘ 𝑌 ) ) ) = ( ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑋 ) ) ∩ ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑌 ) ) ) ) |
| 11 |
2 3
|
diaf11N |
⊢ ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) → 𝐼 : dom 𝐼 –1-1-onto→ ran 𝐼 ) |
| 12 |
11
|
adantr |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → 𝐼 : dom 𝐼 –1-1-onto→ ran 𝐼 ) |
| 13 |
|
simprl |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → 𝑋 ∈ ran 𝐼 ) |
| 14 |
|
f1ocnvfv2 |
⊢ ( ( 𝐼 : dom 𝐼 –1-1-onto→ ran 𝐼 ∧ 𝑋 ∈ ran 𝐼 ) → ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑋 ) ) = 𝑋 ) |
| 15 |
12 13 14
|
syl2anc |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑋 ) ) = 𝑋 ) |
| 16 |
|
simprr |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → 𝑌 ∈ ran 𝐼 ) |
| 17 |
|
f1ocnvfv2 |
⊢ ( ( 𝐼 : dom 𝐼 –1-1-onto→ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) → ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑌 ) ) = 𝑌 ) |
| 18 |
12 16 17
|
syl2anc |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑌 ) ) = 𝑌 ) |
| 19 |
15 18
|
ineq12d |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑋 ) ) ∩ ( 𝐼 ‘ ( ◡ 𝐼 ‘ 𝑌 ) ) ) = ( 𝑋 ∩ 𝑌 ) ) |
| 20 |
10 19
|
eqtr2d |
⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑋 ∈ ran 𝐼 ∧ 𝑌 ∈ ran 𝐼 ) ) → ( 𝑋 ∩ 𝑌 ) = ( 𝐼 ‘ ( ( ◡ 𝐼 ‘ 𝑋 ) ∧ ( ◡ 𝐼 ‘ 𝑌 ) ) ) ) |