" 26.If "m=(cos alpha)/(cos beta)" and "n=(cos alpha)/(sin beta)," show that "(m^(2)+n^(2))cos^(2)beta=n^(2)

If (cos alpha)/(cos beta)=m and (cos alpha)/(sin beta)=n show that (m^(2)+n^(2))cos^(2)beta=n^(2)

If n=(cos alpha)/(cos beta),m=(sin alpha)/(sin beta) then (m^(2)-n^(2))sin^(2)beta is

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

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 : (cos^4 beta)/(cos^2 alpha)+ (sin^4 beta)/ (sin^2 alpha) =1 .

If sin alpha+sin beta=a and cos alpha+cos beta=b show that sin(alpha+beta)=(2ab)/(alpha^(2)+beta^(2))

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

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