`If cos 2 theta = - 1/2, "find the value of" cos theta`

If 2 cos theta = 1 , find the value of 2 theta

If cos theta=(1)/(2), find the value of (2sec theta)/(1+tan^(2)theta)

If 2 sin theta cos theta = 1 , then find the value of sin theta-cos theta .

If sec theta=4 , find the value of cos theta/(4cos^2 theta+3sin^2 theta) .

If 3cot theta=4, find the value of (4cos theta-sin theta)/(2cos theta+sin theta)

If sin theta_1 + sintheta_2 + sin theta_3 = 3 then find the value of cos theta_1 + cos theta_2 + cos theta_3.

If sin theta_1 + sintheta_2 + sin theta_3 = 3 then find the value of cos theta_1 + cos theta_2 + cos theta_3.

If 3cos theta=1, find the value of (6sin^(2)theta+tan^(2)theta)/(4cos theta)

If cos theta=(5)/(13), find the value of (sin^(2)theta-cos^(2)theta)/(2sin theta cos theta)xx(1)/(tan^(2)theta)