Prove that `5costheta+3cos(theta+pi/3)+3` lies between `-4a n d10.`

Prove that cos 3x=4 cos ^3x-3cos x

Prove that: cos3x=4cos^(3)x-3cosx

Solve cos theta * cos 2 theta * cos 3 theta = (1)/( 4), 0 le theta le pi

Prove that (sin 3 theta)/(1+2cos2 theta)=sin theta and hence find sin15^(@)

Prove that (sin 3 theta)/(1+2cos2 theta)=sin theta and hence find sin15^(@)

Solve 7 cos^(2) theta+3 sin^(2) theta=4 .

Prove that log_(10) 2" lies between " 1/4 and 1/3 .

Prove that: (sin^(3) theta + cos^(3) theta)/(sin theta + cos theta) = 1-sin theta cos theta

Number of solutions of the equation cot( theta ) + cot( theta +(pi)/(3))+ cos ( theta -(pi)/(3))+ cot( 3 theta ) =0 , where theta in ( 0,(pi)/(2))

Prove that (cos^(2) theta)/(1-tan theta)+(sin^(3) theta)/(sin theta - cos theta) =1 + sin theta cos theta .