Find all solutions on the interval $\displaystyle {\left[{0},{2}\pi\right)}$. Give exact answers. 

 $\displaystyle {{\sin}^{{2}}{\left({x}\right)}}-{{\cos}^{{2}}{\left({x}\right)}}-{\cos{{\left({x}\right)}}}={0}$ 

Separate multiple solutions with a comma. If there are no solutions please enter, "no solution" exactly.