\[1)\ 2(1 + i) + 3 - 7i =\]
\[= 2 + 2i + 3 - 7i = 5 - 5i;\]
\[2)\ (2 + i)( - 3 - 2i) + 1 + 11i =\]
\[= - 6 - 4i - 3i + 2 + 1 + 11i =\]
\[= - 3 + 4i;\]
\[3)\ 2i(1 + i) + 4i\left( 2 - \frac{1}{2}i \right) =\]
\[= 2i - 2 + 8i + 2 = 10i;\]
\[4)\ ( - 3 + 4i)2i + ( - 2 - 7i)( - 3i) =\]
\[= - 6i - 8 + 6i - 21 = - 29;\]
\[5)\ \left( \sqrt{3} + 2i \right)\left( \sqrt{3} - i \right) + 1 - 4\sqrt{3}i =\]
\[= 3 + \sqrt{3}i + 2 + 1 - 4\sqrt{3}i =\]
\[= 6 - 3\sqrt{3}i;\]
\[6)\ \frac{1}{3}i(6 - 12i) + \frac{1}{4}i(4 + 8i) =\]
\[= 2i + 4 + i - 2 = 2 + 3i.\]