Пожалуйста помогите!!!❤❤❤❤

А) sin2×75°=sin150°=1/2
б)
$\sin(2 \times \frac{\pi}{8} ) = \sin( \frac{\pi}{4} ) = \frac{ \sqrt{2} }{2}$
в)
$\frac{1}{2} \sin(2 \times {15}^{0} ) = \frac{1}{2} \sin( {30}^{0} ) = \\ = \frac{1}{2} \times \frac{1}{2} = \frac{1}{4}$
${ \cos }^{2} \frac{\pi}{8} + 2 \cos( \frac{\pi}{8} ) \times \sin( \frac{\pi}{8} ) + \\ + { \sin}^{2} \frac{\pi}{8} = \sin(2 \times \frac{\pi}{8} ) + 1= \\ = \sin( \frac{\pi}{4} ) + 1 = \frac{ \sqrt{2} }{2} + 1$
д)

${ \sin}^{2} \frac{\pi}{12} - 2 \sin( \frac{\pi}{12} ) \times \cos( \frac{\pi}{12} ) + \\ + { \cos}^{2} \frac{\pi}{12} = 1\ - sin(2 \times \frac{\pi}{12} ) = \\ = 1 - \sin( \frac{\pi}{6} ) = 1 - \frac{1}{2} = \frac{1}{2}$
е)
$\cos(2 \times {75}^{0} ) = \cos( {150}^{0} ) = \frac{1}{2}$
ж)

$\cos( 2 \times \frac{\pi}{8} ) = \cos( \frac{\pi}{4} ) = \frac{ \sqrt{2} }{2}$
з)
$- \cos(2 \times \frac{\pi}{12} ) = - \cos( \frac{\pi}{6} ) = - \frac{ \sqrt{3} }{2}$