A piecewise function is defined as shown.

[tex]\[ f(x)=\left\{
\begin{array}{cc}
-x, & x \leq -1 \\
1, & x = 0 \\
x+1, & x \geq 1
\end{array}\right. \][/tex]

What is the value of [tex]\( f(x) \)[/tex] when [tex]\( x = 3 \)[/tex] ?

A. [tex]\( -3 \)[/tex]

B. [tex]\( -2 \)[/tex]

C. 1

D. 4



Answer :

To determine the value of the piecewise function [tex]\( f(x) \)[/tex] at [tex]\( x = 3 \)[/tex], we need to identify which condition [tex]\( x = 3 \)[/tex] satisfies and then apply the corresponding function definition.

The piecewise function given is:
[tex]\[ f(x) = \begin{cases} -x, & \text{if } x \leq -1 \\ 1, & \text{if } x = 0 \\ x + 1, & \text{if } x \geq 1 \end{cases} \][/tex]

Let's evaluate each condition for [tex]\( x = 3 \)[/tex]:

1. [tex]\( x \leq -1 \)[/tex]:
- For this condition to be true, [tex]\( x \)[/tex] must be less than or equal to [tex]\(-1\)[/tex]. Since [tex]\( 3 \)[/tex] is not less than or equal to [tex]\(-1\)[/tex], this condition does not apply.

2. [tex]\( x = 0 \)[/tex]:
- For this condition to be true, [tex]\( x \)[/tex] must be exactly [tex]\( 0 \)[/tex]. Since [tex]\( 3 \)[/tex] is not equal to [tex]\( 0 \)[/tex], this condition does not apply.

3. [tex]\( x \geq 1 \)[/tex]:
- For this condition to be true, [tex]\( x \)[/tex] must be greater than or equal to [tex]\( 1 \)[/tex]. Since [tex]\( 3 \)[/tex] is greater than [tex]\( 1 \)[/tex], this condition applies.

Since [tex]\( 3 \)[/tex] meets the third condition [tex]\( x \geq 1 \)[/tex], we use the corresponding function rule [tex]\( x + 1 \)[/tex]:

[tex]\[ f(3) = 3 + 1 \][/tex]

Perform the calculation:

[tex]\[ f(3) = 4 \][/tex]

Therefore, the value of [tex]\( f(x) \)[/tex] when [tex]\( x = 3 \)[/tex] is [tex]\( 4 \)[/tex].

The correct answer is [tex]\(\boxed{4}\)[/tex].