Вычислите: а) (2√2)^-2 / 2, б) (√27 - √48)√12, в) (√2+√18)^2 / 16, г) 2^3 · 16^-1/2, д) 12^-2,8 · 4^1,8 : 3^-4,8, е) (5^4/7 · 11^2/3)^21 / 55^12

а) $\frac{(2\sqrt{2})^{-2}}{2} = \frac{2^{-2} \cdot (\sqrt{2})^{-2}}{2} = \frac{\frac{1}{4} \cdot \frac{1}{2}}{2} = \frac{\frac{1}{8}}{2} = \frac{1}{16} = 0,0625$ б) $(\sqrt{27} - \sqrt{48})\sqrt{12} = \sqrt{27 \cdot 12} - \sqrt{48 \cdot 12} = \sqrt{324} - \sqrt{576} = 18 - 24 = -6$ в) $\frac{(\sqrt{2} + \sqrt{18})^2}{16} = \frac{(\sqrt{2} + 3\sqrt{2})^2}{16} = \frac{(4\sqrt{2})^2}{16} = \frac{16 \cdot 2}{16} = 2$ г) $2^3 \cdot 16^{-0,5} = 2^3 \cdot (2^4)^{-0,5} = 2^3 \cdot 2^{-2} = 2^{3-2} = 2^1 = 2$ д) $12^{-2,8} \cdot 4^{1,8} : 3^{-4,8} = (3 \cdot 4)^{-2,8} \cdot 4^{1,8} \cdot 3^{4,8} = 3^{-2,8} \cdot 4^{-2,8} \cdot 4^{1,8} \cdot 3^{4,8} = 3^{-2,8+4,8} \cdot 4^{-2,8+1,8} = 3^2 \cdot 4^{-1} = 9 \cdot \frac{1}{4} = 2,25$ е) $\frac{(5^{\frac{4}{7}} \cdot 11^{\frac{2}{3}})^{21}}{55^{12}} = \frac{5^{\frac{4}{7} \cdot 21} \cdot 11^{\frac{2}{3} \cdot 21}}{55^{12}} = \frac{5^{12} \cdot 11^{14}}{55^{12}} = \frac{5^{12} \cdot 11^{12} \cdot 11^2}{55^{12}} = \frac{(5 \cdot 11)^{12} \cdot 121}{55^{12}} = \frac{55^{12} \cdot 121}{55^{12}} = 121$