(six+2cosx)/(2sinx+cosx)=5/4
4sinx+8cosx=10sinx+5cosx
8cosx-5cosx=10sinx-4sinx
3cosx=6sinx
cosc=2sinx
(2sin²x+sinxcosx+3sin²x+3cos²x)/(cos²x+2sinxcosx+sin²x+cos²x)=
=(5sin²x+sinxcosx+3cos²x)/(2cos²x+2sinxcosx+sin²x)=
=(5sin²x+2sin²x+12sin²x)/(8sin²x+4sin²x+sin²x)=19sin²x/13sin²x)=19/13