Question

giải các phương trình sau :

a) sin(x−\(\frac{2\pi}{3}\))=cos2x ; b) tan(2x+45^o)tan(180^o−\(\frac{x}{2}\))=1 ; c) cos2x−sin²x=0 ; d) 5tanx−2cotx=3 ; e)

sin2x+sin²x=\(\frac{1}{2}\) ; f) sin²\(\frac{x}{2}\)+sinx−2cos²\(\frac{x}{2}\)=\(\frac{1}{2}\) ; g) \(\frac{1+\cos2x}{\cos x}\)=\(\frac{\sin2x}{1-\cos2x}\)