निम्न समीकरणों को हल कीजिए -
`cos5theta=cos4theta`

4cos6 theta cos4 theta cos2 theta=

4 cos 6 theta cos 4 theta cos 2 theta =

Solve cos2theta+cos8theta=cos5theta

If cos theta = cos 5pi//4 , then theta =

Prove that (tan 5theta + tan 3theta)/(tan 5theta - tan 3theta) = 4 cos 2theta cos 4theta

IF 11 theta = pi then cos theta . cos 2 theta . cos 3 theta cos 4 theta . Cos 5 theta is

If 13 theta =pi , " prove that " cos theta cos 2theta cos3 theta cos4theta cos5 theta cos6 theta =1/2^(6)

Prove the following identities : (sin theta +sin 3 theta + sin 5 theta + sin 7theta)/(cos theta + cos 3 theta + cos 5 theta + cos 7 theta)=tan 4 theta

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).

Prove that 16 cos ^(5) theta - 20 cos ^(3) theta + 5 cos theta = cos 5 theta.