Metamath Proof Explorer


Theorem csbov2g

Description: Move class substitution in and out of an operation. (Contributed by NM, 12-Nov-2005)

Ref Expression
Assertion csbov2g ( 𝐴𝑉 𝐴 / 𝑥 ( 𝐵 𝐹 𝐶 ) = ( 𝐵 𝐹 𝐴 / 𝑥 𝐶 ) )

Proof

Step Hyp Ref Expression
1 csbov12g ( 𝐴𝑉 𝐴 / 𝑥 ( 𝐵 𝐹 𝐶 ) = ( 𝐴 / 𝑥 𝐵 𝐹 𝐴 / 𝑥 𝐶 ) )
2 csbconstg ( 𝐴𝑉 𝐴 / 𝑥 𝐵 = 𝐵 )
3 2 oveq1d ( 𝐴𝑉 → ( 𝐴 / 𝑥 𝐵 𝐹 𝐴 / 𝑥 𝐶 ) = ( 𝐵 𝐹 𝐴 / 𝑥 𝐶 ) )
4 1 3 eqtrd ( 𝐴𝑉 𝐴 / 𝑥 ( 𝐵 𝐹 𝐶 ) = ( 𝐵 𝐹 𝐴 / 𝑥 𝐶 ) )