# Math Help - Solving a trig equation #2

1. ## Solving a trig equation #2

Could anyone help on this trig identity? I have a quiz tomorrow and am unsure on this one.

2 cos squared x- 5 cosx+ 2= 0

Any help is appreciated!

2. Do you mean solve this equation for $\displaystyle x$ ?

If so make $\displaystyle u=\cos x$ and solve the quadratic $\displaystyle 2u^2-5u+2=0$

3. Originally Posted by powerduffgirL
Could anyone help on this trig identity? I have a quiz tomorrow and am unsure on this one.

2 cos squared x- 5 cosx+ 2= 0
... recommend you find out the difference between identities and conditional equations.