Maximum Sum of . . . .
Geometry
Level
2
In a , what is the maximum value of Cos(6A) + Cos(6B) + Cos (6C)?
The answer is 3.
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1 solution
The maximum value of cosinus function is 1, yet cos 6A = cos 6B = cos 6C = 1 is fulfilled when ABC is an equilateral triangle. Hence, the maximum value is 3.