Metamath Proof Explorer


Theorem rneq

Description: Equality theorem for range. (Contributed by NM, 29-Dec-1996)

Ref Expression
Assertion rneq ( 𝐴 = 𝐵 → ran 𝐴 = ran 𝐵 )

Proof

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 )