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

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