Precalculus Examples

$f (x) = {\begin{cases} - x + 6 & x < 1 \\ - 5 & x = 1 \\ x + 4 & x > 1 \end{cases}$ Find $f (1)$

Step 1

Identify the piece that describes the function at $x = 1$ . In this case, $x = 1$ falls within the interval $x = 1$ , therefore use $- 5$ to evaluate $f (1)$ .

$f (x) = {\begin{cases} - x + 6 & x < 1 \\ - 5 & x = 1 \\ x + 4 & x > 1 \end{cases}$

Step 2

The function is equal to $- 5$ at $x = 1$ .

$f (x) = - 5 (]_{x = 1}^{})$

Step 3

Evaluate the function at $x = 1$ .

$f (1) = - 5$