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Which step is included in the graph of the function f(x)=[x-17?

O y=-5 for-4≤x<-3
O y=-2 for -2≤x<-1
O y=-2 for -2 O y=-5 for -4

User Alexmeia
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1 Answer

1 vote

Answer:

y = -2 for -2 < x ≤ -1

Explanation:

Ceiling function


f(x) = \left\lceil x \right\rceil

The least integer that is greater than or equal to x.

Given ceiling function:


f(x) =\left\lceil x-1 \right\rceil

Evaluate values in the given intervals.


\boxed{-4 \leq x < -3}


\implies f(-4) =\left\lceil -4-1 \right\rceil=\left\lceil -5 \right\rceil=-5


\implies f(-3.1) =\left\lceil -3.1-1 \right\rceil=\left\lceil -4.1 \right\rceil=-4


\boxed{-2 \leq x < -1}


\implies f(-2) =\left\lceil -2-1 \right\rceil=\left\lceil -3 \right\rceil=-3


\implies f(-1.1) =\left\lceil -1.1-1 \right\rceil=\left\lceil -2.1\right\rceil=-2


\boxed{-2 < x \leq -1}


\implies f(-1.9) =\left\lceil -1.9-1 \right\rceil=\left\lceil -2.9 \right\rceil=-2


\implies f(-1) =\left\lceil -1-1 \right\rceil=\left\lceil -2 \right\rceil=-2


\boxed{-4 < x \leq -3}


\implies f(-3.9) =\left\lceil -3.9-1 \right\rceil=\left\lceil -4.9 \right\rceil=-4


\implies f(-3) =\left\lceil -3-1 \right\rceil=\left\lceil -4\right\rceil=-4

Therefore, the step that is included in the graph of the given ceiling function is: y = -2 for -2 < x ≤ -1.

Graph of the parent ceiling function f(x) = ⌈x⌉

The graph of the parent function has open dots at (x, x+1) and closed dots at (x, x). Each segment is joined with a horizontal line (step).

The open dot means the value is not included, whereas the closed dot means the value is included.

To graph the given ceiling function f(x) = ⌈x - 1⌉

(See attachment).

  • The y-value is 1 less than the parent function, therefore place open dots at (x, x) and closed dots at (x, x-1).
  • Join each segment with a line (step).

From inspection of the attached graph of the given ceiling function:

  • The step for y = -5 is -5 < x ≤ -4 (shown in blue).
  • The step for y = -2 is -2 < x ≤ -1 (shown in red).

This proves that the only step that is included in the graph of the given ceiling function from the given answer options is:

  • y = -2 for -2 < x ≤ -1
Which step is included in the graph of the function f(x)=[x-17? O y=-5 for-4≤x&lt-example-1
Which step is included in the graph of the function f(x)=[x-17? O y=-5 for-4≤x&lt-example-2
User JamesRat
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3.8k points