The value of `cos^2 20^@ – sin^2 100^@ + cos20^@ cos100^@` is -

The value of cos 20^(@) + Cos 100^(@) + cos 140^(@) is

The value of cos 10^@ sin 20^@ is ________.

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

The value of cos 20^(@) + cos 100^(@) + cos 140^(@) is equal to a) (1)/(2) b) (1)/(sqrt(3)) c) sqrt(3) d)0

The value of 2(cos^(2)20^(@)+cos^(2)140^(@)+cos^(2)100^(@)) is

The value of 2(cos^(2)20^(@)+cos^(2)140^(@)+cos^(2)100^(@)) is

The value of 2(cos^(2)20^(@)+cos^(2)140^(@)+cos^(2)100^(@)) is

The value of (sin^2 20^@ + cos^4 20^@)/(sin^4 20^@+cos^2 20^@) is