" 9.If "cos theta=(1)/(2)(a+(1)/(a))," then the value of "cos3 theta" is ":

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

If cos theta = 1/2 (a+(1)/(a)), then the value of cos 3 theta is ............. A) 1/8 (a ^(3) +(1)/(a ^(3))) B) 3/2 (a+(1)/(a)) C) 1/2 (a^(3) + (1)/(a^(3))) D) 1/3 (a^(3) +(1)/(a ^(3)))

If 2cos theta+sin theta=1 then the value of 4cos theta+3sin theta is

If 2cos 3theta=1 , then the value of theta is

If (1-cos2 theta)/(1+cos2 theta)=3, then the general value of theta is

If cos^(4)theta-sin^(4)theta=(2)/(3) , then the value of 2cos^(2)theta-1 is

If cos theta=(1)/(2)(a+(1)/(a)) then show that cos3 theta=(1)/(2)(a^(3)+(1)/(a^(3)))

If cos theta=(-3)/(5),theta in(pi,(3 pi)/(2)), then the value of ((1+sin theta)/(tan theta)+cos2 theta) is

if cos theta_(1) + cos theta_(2) + cos theta_(3)= sin theta_(1) + sin theta_(2) + sin theta_(3)= 0 , then the value of cos (theta_(1) + theta_(2)) + cos (theta_(2) + theta_(3)) + cos (theta_(3) + theta_(1)) is

If sin theta_(1)+sin theta_(2)+sin theta_(3), then find the value of cos theta_(1)+cos theta_(2)+cos theta_(3)