Ответ:

[tex] \frac{(3 + 3 \cos( \alpha ))(2 - 2 \cos( \alpha )) }{5 \sin(2 \alpha ) } = \\ = \frac{6(1 + \cos( \alpha ))(1 - \cos( \alpha ) )}{10 \sin( \alpha ) \cos( \alpha ) } = \\ = 0.6 \frac{ { \sin( \alpha ) }^{2} }{ \sin( \alpha ) \cos( \alpha ) } = \\ = 0.6 \tan( \alpha ) = \\ = \frac{0.6}{ \cot( \alpha ) } = \\ = \frac{0.6}{3} = 0.2[/tex]