Metamath Proof Explorer


Theorem acoscl

Description: Closure for the arccos function. (Contributed by Mario Carneiro, 31-Mar-2015)

Ref Expression
Assertion acoscl ( 𝐴 ∈ ℂ → ( arccos ‘ 𝐴 ) ∈ ℂ )

Proof

Step Hyp Ref Expression
1 acosf arccos : ℂ ⟶ ℂ
2 1 ffvelrni ( 𝐴 ∈ ℂ → ( arccos ‘ 𝐴 ) ∈ ℂ )