Đề bài

Tính: a) \({\left( {\frac{1}{5}} \right)^{ - 2}};\)                   b) \({4^{\frac{3}{2}}};\)                             c) \({\left( {\frac{1}{8}} \right)^{ - \frac{2}{3}}};\)                      d) \({\left( {\frac{1}{{16}}} \right)^{ - 0,75}}.\)

Lời giải chi tiết

a)      \({\left( {\frac{1}{5}} \right)^{ - 2}} = {\left( {{5^{ - 1}}} \right)^{ - 2}} = {5^2} = 25\) b)     \({4^{\frac{3}{2}}} = {\left( {{4^{\frac{1}{2}}}} \right)^3} = {2^3} = 8\) c)      \({\left( {\frac{1}{8}} \right)^{ - \frac{2}{3}}} = {\left( {2{}^{ - 3}} \right)^{ - \frac{2}{3}}} = {2^2} = 4\) d)     \({\left( {\frac{1}{{16}}} \right)^{ - 0,75}} = {\left( {{2^{ - 4}}} \right)^{ - \frac{3}{4}}} = {2^3} = 8\)