1.1. Show that the equation  $2$ sin² $x$$+3$ cos $x$$=0$  can be written in the form  $a$ cos² $x$$+b$ cos $x$$+c=0$ , where $a$, $b$ and $c$ are integers to be found.

1.2. Hence, or otherwise, solve the equation  $2$sin² $x+3$cos $x=0$  for  $-180^{\circ}\leqx\leq180^{\circ}$.