\[\boxed{\mathbf{348}.}\]
\[1)\ (a - 2b)^{6} =\]
\[= a^{6} - 12a^{5}b + 60a^{4}b^{2} -\]
\[- 160a^{3}b^{3} + 240a^{2}b^{4} -\]
\[- 192ab^{5} + 64b^{6}.\]
\[2)\ \left( 1 + \sqrt{2} \right)^{5} = 1 + 5\sqrt{2} + 20 +\]
\[+ 20\sqrt{2} + 20 + 4\sqrt{2} =\]
\[= 41 + 29\sqrt{2}.\]
\[3)\ (1 + 2x)^{5} = 1 + 10x +\]
\[+ 40x^{2} + 80x^{3} + 80x^{4} + 32x^{5}\]
\[4)\ \left( x + \frac{1}{2x} \right)^{8} = x^{8} + 4x^{6} +\]
\[+ 7x^{4} + 7x^{2} + \frac{35}{8} + \frac{7}{4x^{2}} +\]
\[+ \frac{7}{16x^{4}} + \frac{1}{16x^{6}} + \frac{1}{258x^{8}}.\]