集合等号传递性
theorem eqs_tran (x y z: set): $ x = y \imp y = z \imp x = z $;
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | imp_tran | (x = y \imp y = x) \imp (y = x \imp y = z \imp x = z) \imp x = y \imp y = z \imp x = z |
|
| 2 | eqs_sym | x = y \imp y = x |
|
| 3 | 1, 2 | ax_mp | (y = x \imp y = z \imp x = z) \imp x = y \imp y = z \imp x = z |
| 4 | equality | y = x \imp y = z \imp x = z |
|
| 5 | 3, 4 | ax_mp | x = y \imp y = z \imp x = z |