cos20+cos100+cos140

What is cos20^@ + cos 100^@ + cos 140^@ equal to?

the value of cos 20^@ + cos 100^@ + cos 140 ^@ is equal to

Prove that: cos 20^0cos 100^0+cos 100^0cos 140^0-\ cos 140^0cos 200^0=-3/4

Prove that cos20^@ cos40^@ cos80^@=1/8

Prove that: cos 20^0+cos 100^0+cos 140^0=0

cos20^0+cos80^0-sqrt(3)cos50^0 p. -1 cos0^0+cospi/7+cos(2pi)/7+cos(3pi)/7+cos(4pi)/7+cos(5pi)/7+cos(6pi)/7 q. -3/4 cos20^0+cos40^0+cos60^0-4cos10^0cos20^0cos30^0 r. 1 cos20^0cos100^0+cos100^0cos140^0-cos140^0cos200^0 s. 0

cos20^@cos40^@cos80^@=

The value of cos20^@cos40^@cos60^@cos80^@ is equal to

If x=cos10^@cos20^@cos40^@ , then the value of x is

cos 20^(@) + cos 100^(@) + cos 140^(@) =