2 cos 2 x + 1 + 3 = 2 ( 2 + 3 ) sin x cos x 2 cos 2 x + ( 1 + 3 ) sin 2 x + ( 1 + 3 ) cos 2 x 2 ( 2 + 3 ) sin x cos x = 0 ( 1 + 3 ) sin 2 x + ( 3 + 3 ) cos 2 x 2 ( 2 + 3 ) sin x cos x = 0 ( 1 + 3 ) tan 2 x 2 ( 2 + 3 ) tan x + ( 3 + 3 ) = 0 tan x 12 = 2 + 3 ± ( 2 + 3 ) 2 ( 1 + 3 ) ( 3 + 3 ) 1 + 3 = 2 + 3 ± 4 + 4 3 + 3 3 3 3 3 3 1 + 3 = 2 + 3 ± 1 1 + 3 { tan x 1 = 2 + 3 + 1 1 + 3 = 3 + 3 1 + 3 = 3 + 3 1 + 3 1 3 1 3 = 3 x 1 = π 3 + k π tan x 2 = 2 + 3 1 1 + 3 = 1 + 3 1 + 3 = 1 x 2 = π 4 + k π 2 cos^2 x + 1 + sqrt 3 = 2( 2 + sqrt 3) sin x cos x newline newline 2 cos^2 x + (1 + sqrt 3) sin^2 x + (1 + sqrt 3) cos^2 x - 2( 2 + sqrt 3) sin x cos x =0 newline newline (1 + sqrt 3) sin^2 x + (3 + sqrt 3) cos^2 x - 2( 2 + sqrt 3) sin x cos x =0 newline newline (1 + sqrt 3) tan^2 x - 2( 2 + sqrt 3) tan x + (3 + sqrt 3) =0 newline newline tan x_12= { 2+sqrt 3 +- sqrt{(2+ sqrt 3 )^2-(1+sqrt 3) cdot(3+sqrt 3)} } over {1+ sqrt 3 } = { 2+sqrt 3 +- sqrt{4+4 sqrt 3 + 3 - 3 - sqrt 3 - 3 sqrt 3-3} } over {1+ sqrt 3 }= { 2+sqrt 3 +- 1 } over {1+ sqrt 3 } toward "" newline newline toward left lbrace stack{tan x_1 = { 2+sqrt 3 + 1 } over {1+ sqrt 3 } = { 3+sqrt 3 } over {1+ sqrt 3 } = { 3+sqrt 3 } over {1+ sqrt 3 } cdot {{ 1-sqrt 3 } over {1- sqrt 3 }} = sqrt 3 toward x_1 ={ %pi over 3} + k %pi # alignl tan x_2 ={ 2+sqrt 3 - 1 } over {1+ sqrt 3 }={ 1+sqrt 3 } over {1+ sqrt 3 }= 1 toward x_2= { %pi} over 4 + k %pi } right none