Prove that: ` cos ((2pi)/15) . cos ((4pi)/15) . cos ((8pi)/15) . cos ((16pi)/15) = 1/16`

Prove that: cos ((2 pi) / (15)) * cos ((4 pi) / (15)) * cos ((8 pi) / (15)) * cos ((16 pi) / (15)) = (1) / (16)

Show that 16cos((2 pi)/(15))cos((4 pi)/(15))cos((8 pi)/(15))cos((16 pi)/(15))=1

The value of cos((2pi)/(15))cos((4pi)/(15))cos((8pi)/(15))cos((14pi)/(15)), is

Prove that cos((2pi)/7) cos((4pi)/7) cos((8pi)/7) =1/8

Prove that cos(2 pi)/(15)cos(4 pi)/(15)cos(8 pi)/(15)cos(14 pi)/(15)=(1)/(16)

Prove that cos((2pi)/7)cos((4pi)/7)cos((8pi)/7)=1/8

The value of cos((pi)/(15))cos((2 pi)/(15))cos((4 pi)/(15))cos((8 pi)/(15))=

Prove that :16cos2(pi)/(15)cos4(pi)/(15)cos8(pi)/(15)cos16(pi)/(15)=1

The numerical value of cos(( pi)/15)* cos ((2pi)/15)* cos ((4pi)/15) cos ((7pi)/15) = ...........

Prove that: cos^(2)pi/8 + cos^(2)(3pi)/(8) + cos^(2)(5pi)/(8)+ cos^(2)(7pi)/(8)=2