Common Graphs — Question 4

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Question 4

Sketch the graph of the function: f(x)=x+2−1f(x) = \sqrt{x + 2} - 1

Instructions: Identify the domain, range, intercepts, and transformations applied to the parent square root function. Then provide a sketch.

Original worksheet page 1: question and worked solution for 1-10-004
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Question 4 - Solution

We are given: f(x)=x+2−1f(x) = \sqrt{x + 2} - 1

Step 1: Parent function: f(x)=xf(x) = \sqrt{x}

Transformations:

  • Horizontal shift left by 2: x→x+2x \to x + 2

  • Vertical shift down by 1

Step 2: Domain: x+2≥0⇒x≥−2⇒Domain: [−2,∞)x + 2 \geq 0 \Rightarrow x \geq -2 \Rightarrow \boxed{\text{Domain: } [-2, \infty)}

Step 3: Range: Since square root outputs ≥0\geq 0, and we subtract 1: Range: [−1,∞)\boxed{\text{Range: } [-1, \infty)}

Step 4: Intercepts

  • Y-intercept: f(0)=2−1≈0.414f(0) = \sqrt{2} - 1 \approx 0.414

  • X-intercept: Set f(x)=0⇒x+2=1⇒x+2=1⇒x=−1f(x) = 0 \Rightarrow \sqrt{x + 2} = 1 \Rightarrow x + 2 = 1 \Rightarrow x = -1

Key Point: The graph starts at (−2,−1)(-2, -1)

See the diagram in the original worksheet below.

Original worksheet page 2: question and worked solution for 1-10-004

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