Flashcard 8 - Mathematics: Algebraic Reasoning Flashcard Set for the TSIA2

substitute \(-2\) into all \(x\) of the function \(f(x)\) and simplify to get the answer

When we want to evaluate a function \(f(x)\) at a value \(x=a\), we simply plug in \(a\) into the function. This means substituting \(a\) into all \(x\) of the function given and arriving at an answer. The evaluation of the function \(f(x)\) at \(x=-2\) is shown below.

\[f(x) = x^2 - 2x + 5\] \[f(-2) = (-2)^2 -2(-2) + 5\] \[f(-2) = 4 + 4 + 5\] \[f(-2) = 13\]