If cos 2θ+cos 8θ= cos 5θ then θ=

If 2-cos³ θ=3 sin θ cos θ then θ=

The solution of sin 2θ+cos 2θ+sin θ+ cos θ+1=0 in the first quadrant is

The solution set of sec θ=2cos θ is

If tan² θ=3 cosec² θ-1 then θ=

The domain of Cos^-1 (4x-9) is

If tan (cot x) = cot (tan x), then sin 2x=

If 4 cos θ.cos (120⁰+ θ). Cos (120⁰- θ)=1/2 then θ=

If tan θ+ tan 2θ+tan 3θ= 0 then θ=

If the roots of a(b-c)x²+b(c-a)x+c(a-b)=0 are equal,then a,b,c are in