Arccos -1/2 равен чему?

Question

Arccos -1/2 равен чему?

Answer 1

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Answer 2

Arccoc(-1/2)= π-arccos(1/2)= π-arccos(cos(π/3))= π-π/3= 3*π/3-π/3=(3*π-π)/3= π*(3-1)/3= π*2/3=2*π/3