[(2sinx+1)/(cosx)]*(cosx-sinx)+2=0
Try expanding first by multiplying. After you've done this, you can use trigonometric identities to simplify your equation.
Also attempt to get used to typing with [*TEX] wrappers. it makes your question easier to read.
If you don't understand after showing your work, I'll help further.
$\displaystyle \frac{2sin(x)+1}{cos(x)}*[cos(x)-sin(x)]+2 = 0$