Giải PT

a1)  \(\dfrac{\left(1-2\sin x\right)\cos x}{\left(1+2\sin x\right)\left(1-\sin x\right)}=\sqrt{3}\)

a2) \(2\sin17x+\sqrt{3}\cos5x+\sin5x=0\)

a3) \(\)\(\cos7x-\sin5x=\sqrt{3}\left(\cos5x-\sin7x\right)\)

a4) \(\sqrt{3}\cos5x-2\sin3x\cos2x-\sin x=0\)

a5) \(\tan x+\cot x=2\left(\sin2x+\cos2x\right)\)

Giải PT

a1) \(3.\cos4x-2^{ }\cos^23x=1\)

a2) \(2\cos2x-8\cos x+7=\dfrac{1}{\cos x}\)

a3) \(\dfrac{\left(1+\sin x+\cos2x\right)\sin\left(x+\dfrac{\pi}{4}\right)}{1+\tan x}=\dfrac{1}{\sqrt{2}}\cos x\)

a4) \(9\sin x+6\cos x-3\sin2x+\cos2x=8\)