Proof of Theorem unrab
| Step | Hyp | Ref
| Expression |
| 1 | | unab 1691 |
. . 3
⊢ ({x∣(x
∈ A ∧ φ)} ∪ {x∣(x
∈ A ∧ ψ)}) = {x∣((x
∈ A ∧ φ) ∨ (x ∈ A ∧
ψ))} |
| 2 | | andi 456 |
. . . . 5
⊢ ((x
∈ A ∧ (φ ∨ ψ)) ↔ ((x ∈ A ∧
φ) ∨ (x ∈ A ∧
ψ))) |
| 3 | 2 | biabi 1181 |
. . . 4
⊢ {x∣(x
∈ A ∧ (φ ∨ ψ))} = {x∣((x
∈ A ∧ φ) ∨ (x ∈ A ∧
ψ))} |
| 4 | 3 | cleqcomi 1105 |
. . 3
⊢ {x∣((x
∈ A ∧ φ) ∨ (x ∈ A ∧
ψ))} = {x∣(x
∈ A ∧ (φ ∨ ψ))} |
| 5 | 1, 4 | eqtr 1119 |
. 2
⊢ ({x∣(x
∈ A ∧ φ)} ∪ {x∣(x
∈ A ∧ ψ)}) = {x∣(x
∈ A ∧ (φ ∨ ψ))} |
| 6 | | df-rab 1208 |
. . 3
⊢ {x
∈ A∣φ} = {x∣(x
∈ A ∧ φ)} |
| 7 | | df-rab 1208 |
. . 3
⊢ {x
∈ A∣ψ} = {x∣(x
∈ A ∧ ψ)} |
| 8 | 6, 7 | uneq12i 1609 |
. 2
⊢ ({x
∈ A∣φ} ∪ {x ∈ A∣ψ})
= ({x∣(x ∈ A ∧
φ)} ∪ {x∣(x
∈ A ∧ ψ)}) |
| 9 | | df-rab 1208 |
. 2
⊢ {x
∈ A∣(φ ∨ ψ)} = {x∣(x
∈ A ∧ (φ ∨ ψ))} |
| 10 | 5, 8, 9 | 3eqtr4 1126 |
1
⊢ ({x
∈ A∣φ} ∪ {x ∈ A∣ψ})
= {x ∈ A∣(φ
∨ ψ)} |