Tìm giá trị của x, biết: (12/25)^x = (3/5)^2 - (-3/5)^4

\[{\left( {\frac{{12}}{{25}}} \right)^x} = {\left( {\frac{3}{5}} \right)^2} - {\left( { - \frac{3}{5}} \right)^4}\]

\[{\left( {\frac{{12}}{{25}}} \right)^x} = \frac{9}{{25}} - \frac{{81}}{{625}}\]

\[{\left( {\frac{{12}}{{25}}} \right)^x} = \frac{{144}}{{625}}\]

\[{\left( {\frac{{12}}{{25}}} \right)^x} = {\left( {\frac{{12}}{{25}}} \right)^2}\]

Suy ra x = 2

Vậy x = 2.