Theorem ofeq

Description: Equality theorem for function operation. (Contributed by Mario Carneiro, 20-Jul-2014)

	Ref	Expression
Assertion	ofeq	⊢ ( 𝑅 = 𝑆 → ∘f 𝑅 = ∘f 𝑆 )

Proof

Step	Hyp	Ref	Expression
1		id	⊢ ( 𝑅 = 𝑆 → 𝑅 = 𝑆 )
2	1	ofeqd	⊢ ( 𝑅 = 𝑆 → ∘f 𝑅 = ∘f 𝑆 )