Solve the equation in the interval [0, 2 $\pi$].
Note: The answer must be a multiple of $\pi$. Note that $\pi$ is already provided in the answer so you must give the appropriate multiple. Give exact answers. No decimal numbers. The answer should be a fraction or an integer. E.g. if the solution is $\frac{\pi}{2}$, the answer should be entered as 1/2. If there is more than one answer enter them separated by commas.

$2\sin t \cos t + \sin t -2 \cos t -1 =0$

t = $\pi$