Using the formula cos 2theta = 2 cos^(2)theta - 1, find the value of cos 30^(@), it is being giv...

1+cos theta=2cos^(2)theta

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

Using the formula cos A =sqrt((1+cos2A)/(2)) , find the value of cos30^(@) , it is given that cos60^(@)=(1)/(2) .

Using the formula, sinA=sqrt((1-cos2A)/(2)) , find the value of sin30^(@) , it being given that cos60^(@)=(1)/(2) .

If 2 cos theta=x+(1)/(x) , find the value of 2cos 3 theta

If the angle theta=-30^(@) , find the value of cos theta .

If cos theta = 1/2 (a+(1)/(a)), then the value of cos 3 theta is

if sin theta=cos theta, then find the value of 2tan theta+cos^(2)theta

If sin theta = cos theta , then find the value of 2 tan theta + cos^(2) theta .

If sintheta+sin^(2)theta=1 , then find the value of cos^(2)theta+cos^(4)theta .