Выполните действия: (5a+1/3*b)(5a-1/3*b).

\[\left( 5a + \frac{1}{3}b \right)\left( 5a - \frac{1}{3}b \right) =\]

\[= (5a)^{2} - \left( \frac{1}{3}b \right)^{2} =\]

\[= 25a^{2} - \frac{1}{9}b^{2}.\]