Simplify the expression: (5a + 2b)(5a - 2b)

Solution:

This expression is in the form of a difference of squares, which is \( (x+y)(x-y) = x^2 - y^2 \).

In this case, \( x = 5a \) and \( y = 2b \).

Applying the formula:

\[ (5a + 2b)(5a - 2b) = (5a)^2 - (2b)^2 \]

\[ (5a)^2 = 25a^2 \]

\[ (2b)^2 = 4b^2 \]

So, the simplified expression is:

\[ 25a^2 - 4b^2 \]

Ответ: \( 25a^2 - 4b^2 \).