If `cosa+cosbeta=a ,sina+sinbeta=b` are `alpha-beta=2theta` , then `(cos 3 theta)/(cos3theta)=`

If cosalpha+cosbeta=a ,sinalpha+sinbeta=b and alpha-beta=2theta, then (cos3theta)/(costheta)=

If cosalpha+cosbeta=a,sinalpha+sinbeta=band alpha-beta=2theta , then (cos3theta)/(costheta) =

Ifcos alpha+cos beta=a,sin alpha+sin beta=b and alpha-beta=2 theta then (cos3 theta)/(cos theta)=

If cos alpha+ cos beta= a, sin alpha+ sin beta= b and alpha- beta= 2 theta . Then (cos 3 theta)/(cos theta)=

If cos alpha+cos beta=a*sin alpha+sin beta=b and alpha-beta=2 theta then (cos3 theta)/(cos theta)=

If cos alpha+cos beta=a sin alpha+sin beta=balpha-beta=2 theta then (cos3 theta)/(cos theta)=

If cos alpha + cosbeta=a, sinalpha + sinbeta=b and theta is the arithmetic mean between alpha and beta , then (sin2theta + cos 2theta) is equal to :

If cos alpha + cosbeta=a, sinalpha + sinbeta=b and theta is the arithmetic mean between alpha and beta , then (sin2theta + cos 2theta) is equal to :

If cos alpha + cos beta = a, sin alpha + sin beta = b and theta is the arithmetic mean between alpha and beta then sin 2 theta + cos 2 theta is equal to