Prove that `sqrt(2+sqrt(2+2cos4 theta))=2cos theta`

Prove that: \ sqrt(2+sqrt(2+2cos4theta))=2costheta

Show that sqrt[2+sqrt[2+2cos4theta]]=2costheta

Prove that sqrt ( 2 + sqrt (2 + sqrt (2 + 2 cos 8 theta))) = 2 cos theta, where theta in [ (-pi)/(8), (pi)/(8)]

Show that: sqrt(2+sqrt(2+sqrt(2+2cos8theta)))=2costheta,0

Prove that : (sin^(2)theta)/(cos theta)+cos theta=sec theta

Prove that : (2 cos 2^n theta + 1)/(2 cos theta +1) = (2 cos theta -1) (2 cos 2theta -1) (2 cos 2^2 theta -1) … (2 cos 2^(n-1) theta -1)

Prove that sqrt((1-cos2theta)/(1+cos2theta))=tantheta where tantheta>0

Prove that ( cos theta + cos 2 theta + cos 3 theta + cos 4 theta)/(sin theta + sin 2 theta + sin 3 theta + sin 4 theta)= cot ""(5theta)/(2).

If 270^@ < theta < 360^@ , then sqrt(2 + sqrt(2 + 2 cos theta)) is equal to

Prove that : (2 cos^(3) theta-cos theta)/(sin theta-2 sin^(3)theta)=cot theta