Two values of ArcCos not showing

Question

When I try to find
θ = ArcCos[-.5]

I am expecting more than one answer: $$2 pi/3, 4pi/3,...$$
But Mathematica is returning only one:
2.0944 and it is not in angle format as well. Is there a way to get all the values of angles in angle format?

Andreas · Accepted Answer

Try the equivalent
Solve[-1/2 == Cos[θ], θ]

and you get multiple values

Conor Cosnett · Answer

you could define a new version of ArcCos[] to produce the desired behaviour
arcCos[θ_] := Solve[θ == Cos[x] , x]

Two values of ArcCos not showing

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