Đề bài

Tìm x, biết:

a) $x:{\left( {\dfrac{{ - 1}}{3}} \right)^3} = \dfrac{{ - 1}}{3}$

b) $x.{\left( {\dfrac{{ - 3}}{7}} \right)^5} = {\left( {\dfrac{{ - 3}}{7}} \right)^7}$

c) ${\left( {\dfrac{{ - 2}}{3}} \right)^{12}}:x = {\left( {\dfrac{{ - 2}}{3}} \right)^9}$

d) ${\left( {x + \dfrac{1}{3}} \right)^2} = \dfrac{1}{{25}}$