Children’s cough syrup has dosage guidelines based on a child’s age. In the following piecewise function, x represents the child’s age in years and f(x) represents the dosage in fluid ounces.

f(x)=⎧⎩⎨⎪⎪0.5 if 1≤x≤31.0 if 3<x≤60.5x if x>6

Does the graph accurately represent the piecewise function? Why or why not?

(1 point)
Responses

Yes, because all of the points at the ends of the pieces of the function should have closed circles.
Yes, because all of the points at the ends of the pieces of the function should have closed circles.

No. The graph should be continuous, with all the pieces connected.
No. The graph should be continuous, with all the pieces connected.

No. There should be an open circle on the first point of two parts of the function.
No. There should be an open circle on the first point of two parts of the function.

Yes. The graph is correct because all three pieces of the function are present.

1 answer

To evaluate whether the graph accurately represents the piecewise function given, we should analyze the endpoints of the defined intervals and how they relate to the function.

The piecewise function is defined as follows:

  • \( f(x) = 0.5 \) if \( 1 \leq x \leq 3 \)
  • \( f(x) = 1.0 \) if \( 3 < x \leq 6 \)
  • \( f(x) = 0.5x \) if \( x > 6 \)

Now, let's consider the continuity and the endpoints of each piece:

  1. For \( f(x) = 0.5 \) in the interval \( [1, 3] \), the endpoints at \( x=1 \) and \( x=3 \) should both be closed circles because it's inclusive (both 1 and 3 are part of this interval).

  2. For \( f(x) = 1.0 \) in the interval \( (3, 6] \), at \( x=3 \) there should be an open circle (indicating that 3 is not included), and at \( x=6 \) there should be a closed circle (since 6 is included in that piece).

  3. For \( f(x) = 0.5x \) in the interval \( (6, \infty) \), at \( x=6 \) there should be an open circle (indicating that 6 is not included), since this part starts right after 6.

With this analysis, we can conclude:

  • There should be an open circle at \( x=3 \) and \( x=6 \) to indicate that those points are not included in the second and third piece of the function, respectively.

Since the function does have open circles at those points, the correct response would be:

No. There should be an open circle on the first point of two parts of the function.