Odpowiedź:
a)
[tex] \sin( - {870}^{o} ) = \sin(2 \times {360}^{o} + {150}^{o} ) = [/tex]
[tex] = - \sin( {150}^{o} ) = - \sin( {180}^{o} - {30}^{o} ) = [/tex]
[tex] = - \sin( {30}^{o} ) = - \frac{1}{2} [/tex]
b)
[tex] \tan( - {330}^{o} ) = - \tan( {360}^{o} - {30}^{o} ) = [/tex]
[tex] = \tan( {30}^{o} ) = \frac{ \sqrt{3} }{3} [/tex]