| Metamath Proof Explorer |
< Previous
Next >
Related theorems Unicode version |
| Description: A useful inference for substituting definitions into an equality. (The proof was shortened by Andrew Salmon, 25-May-2011.) |
| Ref | Expression |
|---|---|
| eqeq12d.1 |
|
| eqeq12d.2 |
|
| Ref | Expression |
|---|---|
| eqeq12d |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eqeq12d.1 |
. 2
| |
| 2 | eqeq12d.2 |
. 2
| |
| 3 | eqeq12 2153 |
. 2
| |
| 4 | 1, 2, 3 | syl11anc 659 |
1
|