If `(cos alpha)/(cos beta)=a `and `(sin alpha)/(sin beta)=b` then the value of `sin^(2)beta` in terms of a and b

If sin alpha-sin beta=a and cos alpha+cos beta=b then write the value of cos(alpha+beta)

If sin alpha-sin beta=a and cos alpha+cos beta=b then write the value of cos(alpha+beta)

If cos alpha + cos beta = 0 = sin alpha + sin beta, then value of cos 2 alpha + cos 2 beta is

If cos alpha+cos beta=0=sin alpha+sin beta then cos2 alpha+cos2 beta=

(cos alpha + cos beta) ^ (2) + (sin alpha + sin beta) ^ (2) =

If sin alpha+sin beta=a and cos alpha-cos beta=b then

If (cos^(4)alpha)/(cos^(2)beta)+(sin^(4)alpha)/(sin^(2)beta)=1 then the value of (cos^(4)beta)/(cos^(2)alpha)+(sin^(4)beta)/(sin^(2)alpha) is

If sinalpha+sin beta=a and cos alpha+cos beta=b,then sin(alpha+beta)=