The value of `cos(pi/7)+cos((2pi)/7)+cos((3pi)/7)+cos((4pi)/7)+cos((5pi)/7)+cos((6pi)/7)+cos((7pi)/7)` is 1 (b) `-1` (c) 0 (d) none of these

cos(pi/7)cos((2pi)/7)cos((4pi)/7)=

cos((2pi)/7)+cos((4pi)/7)+cos((6pi)/7)

The value of cos((2pi)/7)cos((4pi)/7)cos((6pi)/7) is

The value of cos((2pi)/7)+cos((4pi)/7)+cos((6pi)/7)+cos((7pi)/7)=

The value of cos((pi)/(7))+cos((2 pi)/(7))+cos((3 pi)/(7))+cos((4 pi)/(7))+cos((5 pi)/(7))+cos((6 pi)/(7))+cos((7 pi)/(7)) is 1(b)-1(c)0(d) none of these

Find the value of cospi/7+cos(2pi)/7+cos(3pi)/7+cos(4pi)/7+cos(5pi)/7+cos(6pi)/+cos(7pi)/7

the value of (cos pi)/(7)cos(2(pi)/(7))cos(3(pi)/(7)) is

Find the value of cos(2pi)/7+cos(4pi)/7+cos(6pi)/7

Find the value of cos(2pi)/7+cos(4pi)/7+cos(6pi)/7

The value of cos ""pi/7 cos ""(2pi)/(7) cos ""(3pi)/(7) is-