Question

factor.
$u^2 - 4$

Explanation:

Step1: Identify the formula

The expression \( u^2 - 4 \) is a difference of squares, which follows the formula \( a^2 - b^2=(a + b)(a - b) \). Here, \( a = u \) and \( b = 2 \) (since \( 4 = 2^2 \)).

Step2: Apply the formula

Substitute \( a = u \) and \( b = 2 \) into the difference - of - squares formula:
\( u^2-4=u^2 - 2^2=(u + 2)(u - 2) \)

Answer:

\((u + 2)(u - 2)\)