If `a cos^(2) 3 alpha+b cos^(4) alpha=16 cos^(6)alpha+9cos^(2) alpha` is an identity, then

cos alpha cos(60^(@) - alpha ) cos (60^(@) + alpha ) = 1/4 cos 3 alpha.

cos alpha cos 2 alpha cos 4 alpha cos 8 alpha = (1)/(16), if alpha = 24 ^(@)

Which is equivalent to (sin^2 alpha + cos^2 alpha )/(cos alpha ) ?

The expression cos^(2)(alpha + beta + gamma) + cos^(2)(beta + gamma) + cos^(2)alpha - 2cos alpha cos(beta + gamma)cos(alpha + beta + gamma) is (a) independent of alpha (b) independent of beta (c) dependent on gamma only (d) dependent on alpha, beta, gamma

If a cos^3 alpha +3acosalpha*sin alpha = m and a sin^3alpha +3a cos^3alpha sin^3alpha = n then (m + n)^(2/3) + (m-n)^(2/3)

Show that : sin^6 alpha+ cos^6 alpha ge 1/4

cos2 alpha-cos3alpha-cos4alpha+cos5alpha simplifies to :

Show that cos ^2 alpha + cos^2 (alpha +Beta) - 2 cos alpha cos betacos (alpha+ beta) =sin^2 beta

(cos ^(3) alpha - cos 3 alpha )/( cos alpha ) + (sin ^(3)alpha + sin 3 alpha )/( sin alpha ) = 3.

find the value of (cos^3alpha+sin^3alpha)/(1-sin(alpha).cos(alpha))