Respuesta :

Answer:

pi/4 + kpi (choice #1)

Step-by-step explanation:


Answer:[tex]x=\frac{\pi}{4}[/tex]

Step-by-step explanation:

`Writing tan and cos in form of sin

[tex]\frac{sinx}{cosx}-\left ( 1-2sin^2x\right )=2sinxcosx[/tex]

[tex]\frac{sinx}{cosx}-1+2sin^2x=2sinxcosx[/tex]

[tex]\frac{sinx-cosx}{cosx}=2sinx\left ( cosx-sinx\right )[/tex]

[tex]2sinx\left ( cosx-sinx\right )-\frac{sinx-cosx}{cosx}=0[/tex]

[tex]\left ( cosx-sinx\right )\left [ 2sinx+\frac{1}{cosx}\right ]=0[/tex]

[tex]\left ( cosx-sinx\right )\left [ \frac{2sinxcosx+1}{cosx}\right ]=0[/tex]

so cosx-sinx=0 or 2sinxcosx+1=0 and cosx is not equals to zero

cosx-sinx=0

tanx=1,[tex]x=\frac{\pi}{4}[/tex]

similarly

[tex]x=n\pi +\frac{\pi}{4}[/tex]

For 2sinxcosx+1=0

sin2x=-1

[tex]2x=\frac{3\pi}{2}[/tex]

but this value is not satisfied by equation thus

[tex]x=n\pi +\frac{\pi}{4}[/tex]