H
hungtybg
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
1/ cotx+sin[1+tanx.(tanx/2)]=4
2/cos3x+cos2x-cosx-1=0
3/cos^2.3x.cos2x-cos^2.x=0
4/1+sinx+cosx+sin2x+cos2x=0
5/cos^4.x+sin^4.x+cos(x-pi/4).sin(3x-pi/4)-3/2=0
2/cos3x+cos2x-cosx-1=0
3/cos^2.3x.cos2x-cos^2.x=0
4/1+sinx+cosx+sin2x+cos2x=0
5/cos^4.x+sin^4.x+cos(x-pi/4).sin(3x-pi/4)-3/2=0