The value of cos2π12+cos2π4+cos25π12 is
32
23
3+32
23+3
Explanation for correct option
Given trigonometric function is cos2π12+cos2π4+cos25π12
cos2π12=cosπ2-5π122=sin5π122
Therefore,
cos2π12+cos2π4+cos25π12=sin25π12+cos25π12+cos2π4=1+122∵sin2A+cos2A=1&cosπ4=12=1+12=32
Hence, the correct option is OptionA