\( \sin ^ { 2 } ( \frac { 9 \pi } { 8 } + \alpha ) - \sin ^ { 2 } ( \frac { 17 \pi } { 8 } - \alpha ) \)

Fid an angle \( \theta \) coterminal to \( -561^{\circ} \), where \( 0^{\circ} \leq \theta<360^{\circ} \)

Find all solutions of the equation \( 2 \cos x-1=0 \). The answer is \( A+B k \pi \) and \( C+D k \pi \) where \( k \) is any integer, \( 0<A<C<2 \pi \), \( A=\square, D=\square \) \( C=\square \)

Thid an angle 9 coterminal to \( 1066^{\circ} \), where \( 0^{\circ} \leq 0<360 \)

Find an angle \( \theta \) coterminal to \( -555^{\circ} \), where \( 0^{\circ} \leq \theta<360^{\circ} \)

Corvert the following angle from degrees to radians. Express your answer in simplest form.