Proof of Theorem bj-inrab
| Step | Hyp | Ref
| Expression |
| 1 | | an4 656 |
. . . 4
⊢ (((𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝑥 ∈ 𝐵 ∧ 𝜓)) ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝜑 ∧ 𝜓))) |
| 2 | | elin 3947 |
. . . . 5
⊢ (𝑥 ∈ (𝐴 ∩ 𝐵) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵)) |
| 3 | 2 | anbi1i 624 |
. . . 4
⊢ ((𝑥 ∈ (𝐴 ∩ 𝐵) ∧ (𝜑 ∧ 𝜓)) ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝜑 ∧ 𝜓))) |
| 4 | 1, 3 | bitr4i 278 |
. . 3
⊢ (((𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝑥 ∈ 𝐵 ∧ 𝜓)) ↔ (𝑥 ∈ (𝐴 ∩ 𝐵) ∧ (𝜑 ∧ 𝜓))) |
| 5 | 4 | abbii 2801 |
. 2
⊢ {𝑥 ∣ ((𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝑥 ∈ 𝐵 ∧ 𝜓))} = {𝑥 ∣ (𝑥 ∈ (𝐴 ∩ 𝐵) ∧ (𝜑 ∧ 𝜓))} |
| 6 | | df-rab 3420 |
. . . 4
⊢ {𝑥 ∈ 𝐴 ∣ 𝜑} = {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)} |
| 7 | | df-rab 3420 |
. . . 4
⊢ {𝑥 ∈ 𝐵 ∣ 𝜓} = {𝑥 ∣ (𝑥 ∈ 𝐵 ∧ 𝜓)} |
| 8 | 6, 7 | ineq12i 4198 |
. . 3
⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} ∩ {𝑥 ∈ 𝐵 ∣ 𝜓}) = ({𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)} ∩ {𝑥 ∣ (𝑥 ∈ 𝐵 ∧ 𝜓)}) |
| 9 | | inab 4289 |
. . 3
⊢ ({𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)} ∩ {𝑥 ∣ (𝑥 ∈ 𝐵 ∧ 𝜓)}) = {𝑥 ∣ ((𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝑥 ∈ 𝐵 ∧ 𝜓))} |
| 10 | 8, 9 | eqtri 2757 |
. 2
⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} ∩ {𝑥 ∈ 𝐵 ∣ 𝜓}) = {𝑥 ∣ ((𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝑥 ∈ 𝐵 ∧ 𝜓))} |
| 11 | | df-rab 3420 |
. 2
⊢ {𝑥 ∈ (𝐴 ∩ 𝐵) ∣ (𝜑 ∧ 𝜓)} = {𝑥 ∣ (𝑥 ∈ (𝐴 ∩ 𝐵) ∧ (𝜑 ∧ 𝜓))} |
| 12 | 5, 10, 11 | 3eqtr4i 2767 |
1
⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} ∩ {𝑥 ∈ 𝐵 ∣ 𝜓}) = {𝑥 ∈ (𝐴 ∩ 𝐵) ∣ (𝜑 ∧ 𝜓)} |