Description: Equality theorem for range. (Contributed by NM, 29-Dec-1996)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rneq | ⊢ ( 𝐴 = 𝐵 → ran 𝐴 = ran 𝐵 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | cnveq | ⊢ ( 𝐴 = 𝐵 → ◡ 𝐴 = ◡ 𝐵 ) | |
| 2 | 1 | dmeqd | ⊢ ( 𝐴 = 𝐵 → dom ◡ 𝐴 = dom ◡ 𝐵 ) |
| 3 | df-rn | ⊢ ran 𝐴 = dom ◡ 𝐴 | |
| 4 | df-rn | ⊢ ran 𝐵 = dom ◡ 𝐵 | |
| 5 | 2 3 4 | 3eqtr4g | ⊢ ( 𝐴 = 𝐵 → ran 𝐴 = ran 𝐵 ) |