Metamath Proof Explorer


Theorem prodeq1

Description: Equality theorem for a product. (Contributed by Scott Fenton, 1-Dec-2017)

Ref Expression
Assertion prodeq1 ( 𝐴 = 𝐵 → ∏ 𝑘𝐴 𝐶 = ∏ 𝑘𝐵 𝐶 )

Proof

Step Hyp Ref Expression
1 nfcv 𝑘 𝐴
2 nfcv 𝑘 𝐵
3 1 2 prodeq1f ( 𝐴 = 𝐵 → ∏ 𝑘𝐴 𝐶 = ∏ 𝑘𝐵 𝐶 )