Use the image to answer the question.

One solid and one dotted curve are drawn in a coordinate plane. The x-axis ranges from negative 3 to 3 and the y-axis ranges from negative 4 to 2, both by 1-unit increments.

Compare the graphs of f(x)=x+1−−−−−√−2 and g(x)=x+1−−−−−√3−2 . Identify which of the following features is true about the graphs.

(1 point)
Responses

The graphs have the same ranges.
The graphs have the same ranges.

The graphs have the same y-intercept.
The graphs have the same y -intercept.

The graphs have the same x-intercept.
The graphs have the same x -intercept.

The graphs have the same domains.
The graphs have the same domains.
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1 answer

To analyze the functions \( f(x) = \sqrt{x + 1} - 2 \) and \( g(x) = \sqrt{x + 1} + 3 - 2 \), we first simplify \( g(x) \):

\[ g(x) = \sqrt{x + 1} + 1 \]

Now let's find the features of each graph.

  1. Domain:

    • The domain of \( f(x) = \sqrt{x + 1} - 2 \) is \( x + 1 \geq 0 \) which means \( x \geq -1 \). The domain is \( [-1, \infty) \).
    • The domain of \( g(x) = \sqrt{x + 1} + 1 \) is also \( x + 1 \geq 0 \), which gives the same domain \( [-1, \infty) \).
  2. Y-Intercept:

    • The y-intercept for \( f(x) \) is found by evaluating \( f(0) \): \[ f(0) = \sqrt{0 + 1} - 2 = 1 - 2 = -1 \]
    • The y-intercept for \( g(x) \) is found by evaluating \( g(0) \): \[ g(0) = \sqrt{0 + 1} + 1 = 1 + 1 = 2 \]
    • Thus, the y-intercepts are different: \( f(x) \) at \(-1\) and \( g(x) \) at \(2\).
  3. X-Intercept:

    • The x-intercept for \( f(x) \) occurs when \( f(x) = 0 \): \[ \sqrt{x + 1} - 2 = 0 \Rightarrow \sqrt{x + 1} = 2 \Rightarrow x + 1 = 4 \Rightarrow x = 3 \]
    • The x-intercept for \( g(x) \): \[ g(x) = 0 \Rightarrow \sqrt{x + 1} + 1 = 0 \Rightarrow \sqrt{x + 1} = -1 \] This has no solutions since a square root cannot be negative.
    • Thus, the x-intercepts are different: \( f(x) \) has an x-intercept at \( x = 3 \) and \( g(x) \) has none.
  4. Range:

    • The range of \( f(x) \): The function starts at \( -1 \) when \( x = -1 \) and approaches infinity as \( x \) increases, so its range is \( [-1, \infty) \).
    • The range of \( g(x) \): The function starts at \( 2 \) when \( x = -1 \) and also approaches infinity, so its range is \( [2, \infty) \).
    • Thus, the ranges are different.

Comparing all features:

  • The graphs have the same domain.
  • Different y-intercepts.
  • Different x-intercepts.
  • Different ranges.

Conclusion: The statement "The graphs have the same domains" is true.