Cos left( frac pi 4 right) July 8, 2019 16 32 64 128 Cos left ( frac pi 4 right Cos left ( frac 3 pi 4 right Cos left ( frac 5 pi 4 right Cos left ( frac 7 pi 4 right Find the value of cos left frac 25 pi 4 right Cos left(- frac pi 4 right) cos(− 4 π )
