If `(cos^(4)alpha)/(cos^(2) beta) + (sin^(4)alpha)/(sin^(2)beta)` = 1, prove that
`(cos^(4)beta)/(cos^(2) alpha) + (sin^(4)beta)/(sin^(2)alpha)= 1`

If (cos^(4)alpha)/(cos^(2) beta) + (sin^(4)alpha)/(sin^(2)beta) = 1, prove that sin^(4)alpha + sin^(4) beta = 2 sin^(2) alpha sin^(2) beta

If cos alpha + cos beta = 1//2 and sin alpha+ sin beta = 1//3 , then

Prove that (cos alpha+cos beta)^(2)+(sin alpha -sin beta)^(2)=4 cos^(2) ((alpha+beta)/(2))

If ( cos x - cos alpha)/(cos x - cos beta) = ( sin^2 alpha cos beta)/(sin^2 beta cos alpha) then cos x =

If (cos alpha)/(cos A)+(sin alpha)/(sin A)+(sin beta)/(sin A)=1 , where alpha and beta do not differ by an even multiple of pi , prove that (cos alpha cos beta)/(cos^(2)A)+(sin alpha sin beta)/(sin^(2)A)=

If cosalpha+cosbeta+cosgamma=0a n da l sosinalpha+sinbeta+singamma=0, then prove that cos2alpha+cos2beta+cos2gamma =sin2alpha+sin2beta+sin2gamma=0 sin3alpha+sin3beta+sin3gamma=3sin(alpha+beta+gamma) cos3alpha+cos3beta+cos3gamma=3cos(alpha+beta+gamma)

IF cos ( alpha + beta ) =0 then sin ( alpha + 2 beta ) is equal to

If y = (2 sin alpha )/(1 + cos alpha + sin alpha) then, prove that (1 - cos alpha + sin alpha)/(1 + sin alpha) = y .

If cos alpha + cos beta =0 = sin alpha + sin beta , then cos 2 alpha + cos 2 beta is equal to