[tex] \sqrt{0.5} \div (3 \sqrt{ \frac{9}{2} } ) \times ( - \sqrt{ \frac{81}{4} } ) = \sqrt{0.5} \div (3 \sqrt{ \frac{9}{2} } ) \times ( - \frac{9}{2} ) = - \frac{ \sqrt{0.5} }{ \frac{3}{ \sqrt{2} } } \times \frac{3}{2} = - \frac{ \sqrt{1} }{3} \times \frac{3}{2} = - \frac{1}{3} \times \frac{3}{2} = - \frac{1}{2} [/tex]
