If `cos(theta-60^(@)),cos theta,cos(theta+60^(@))` are in "H.P.," then `cos theta=`

If cos(theta-alpha),cos theta,cos(theta+alpha) are in H.P. then cos theta.(sec(alpha))/(2)=

If cos(theta-phi),cos(theta),cos(theta+phi) are in HP, the the value of cos(theta)sec((phi)/(2)) is

If cos (theta - alpha),cos(theta),Cos(theta + alpha) are in H.P. and cos alpha ne 1 , then angle alpha lie in the

If : sin (theta - 30^(@))+cos (theta - 60^(@))=k * sin theta, "then" : k=

If cosec theta + cot theta= p , cos theta = ?

cos theta cos2 theta cos3 theta=(1)/(4)

1+cos2 theta+cos4 theta+cos6 theta=

Solve cos theta+cos 2theta+cos 3theta=0 .

4cos6 theta cos4 theta cos2 theta=