# If 2cos^2x - cosx = 1 , what is the value of x?

Apr 2, 2016

$x = 0$

#### Explanation:

As we know:

$\cos 0 = 1$

Put $x = 0$ in equation:

$2 {\cos}^{2} 0 - \cos 0 = 1$

$2 \cdot 1 - 1 = 1$

$1 = 1$

$L . H . S = R . H . S$