Solution: Substitute $ x = 3 $ into $ f(x) $:

Wed, 06 May 2026 23:51:59 +0000

# Simplifying Functions: A Practical Solution by Substituting $ x = 3 $ into $ f(x) $ When working with mathematical functions, evaluating expressions at specific values is a fundamental step that unlocks deeper understanding and accurate computation. One common and straightforward technique is substituting a given value—such as $ x = 3 $—into a function $ f(x) $. This method not only helps clarify function behavior but also plays a key role in problem-solving across algebra, calculus, and applied mathematics. ## Understanding Function Substitution Substituting $ x = 3 $ into a function means replacing every occurrence of the variable $ x $ with the number 3 in the expression $ f(x) $. For example, if $ f(x) = 2x^2 + 5x - 7 $, substituting $ x = 3 $ leads to: