1.
[tex]( \sqrt{75} + 3 \sqrt{12} - \frac{9}{ \sqrt{3} } ) \times \frac{ \sqrt{3} }{2} = \\ (5 \sqrt{3} + 3 \times 2 \sqrt{3} - \frac{9 \sqrt{3} }{3} ) \times \frac{ \sqrt{3} }{2} = \\ (5 \sqrt{3} + 6 \sqrt{3} - 3 \sqrt{3} ) \times \frac{ \sqrt{3} }{2} = \\ (11 \sqrt{3} - 3 \sqrt{3} ) \times \frac{ \sqrt{3} }{2} = \\8 \sqrt{3} \times \frac{ \sqrt{3} }{2} = \\ 4 \sqrt{3} \times \sqrt{3} = \\ 4 \times 3 = 12[/tex]
2.
[tex] {(0.(3))}^{ - 1} = {( \frac{3}{9} )}^{ - 1} = {( \frac{1}{3} )}^{ - 1} = \frac{3}{1} = 3[/tex]
