| Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
| Mirrors > Home > MPE Home > Th. List > csbeq1a | Structured version Visualization version GIF version | ||
| Description: Equality theorem for proper substitution into a class. (Contributed by NM, 10-Nov-2005.) |
| Ref | Expression |
|---|---|
| csbeq1a | ⊢ (𝑥 = 𝐴 → 𝐵 = ⦋𝐴 / 𝑥⦌𝐵) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | csbid 3912 | . 2 ⊢ ⦋𝑥 / 𝑥⦌𝐵 = 𝐵 | |
| 2 | csbeq1 3902 | . 2 ⊢ (𝑥 = 𝐴 → ⦋𝑥 / 𝑥⦌𝐵 = ⦋𝐴 / 𝑥⦌𝐵) | |
| 3 | 1, 2 | eqtr3id 2791 | 1 ⊢ (𝑥 = 𝐴 → 𝐵 = ⦋𝐴 / 𝑥⦌𝐵) |
| Copyright terms: Public domain | W3C validator |