S
sweet_love8


giải phương trình:
1) ( 1-tgx)( 1+sin2x) = 1+tgx
2) cos^4 x +sin^6 x= cos2x
3) cosx.cos x/2.cos 3x/2 -sinx.sin x/2.sin 3x/2 =1/2
4) cos^3 x +sin x - 3sin^2 x.cosx =0
1) ( 1-tgx)( 1+sin2x) = 1+tgx
2) cos^4 x +sin^6 x= cos2x
3) cosx.cos x/2.cos 3x/2 -sinx.sin x/2.sin 3x/2 =1/2
4) cos^3 x +sin x - 3sin^2 x.cosx =0