Ch. 2 - Graphs and Functions

Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook

Lial 13th Edition

Ch. 2 - Graphs and Functions

Problem 99

Chapter 3, Problem 99

Each of the following graphs is obtained from the graph of ƒ(x)=|x| or g(x)=√x by applying several of the transformations discussed in this section. Describe the transformations and give an equation for the graph.

Verified step by step guidance

Step 1: Identify the base function. The graph resembles the shape of the square root function \(g(x) = \sqrt{x}\), but it is shifted and reflected.

Step 2: Observe the horizontal shift. The graph starts at \(x = -4\), indicating a shift to the left by 4 units. This suggests the inside of the square root is \((x + 4)\).

Step 3: Observe the vertical shift and reflection. The graph is below the x-axis, indicating a reflection across the x-axis (a negative sign in front of the function) and a vertical shift downward. The starting point is at \(y = -4\), so the function is shifted down by 4 units.

Step 4: Write the transformed function using the observations: \(y = -\sqrt{x + 4} - 4\).

Step 5: Verify the transformations: The graph is the square root function shifted left 4 units, reflected over the x-axis, and shifted down 4 units.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Video duration:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Square Root Function and Its Graph

The square root function, g(x) = √x, produces a curve starting at the origin (0,0) and increasing slowly to the right. It is defined only for x ≥ 0, and its graph is a half-parabola lying in the first quadrant. Understanding this base graph is essential for identifying transformations.

Transformations of Functions

Transformations include shifts, reflections, stretches, and compressions applied to the base graph. Horizontal shifts move the graph left or right, vertical shifts move it up or down, reflections flip it across axes, and stretches/compressions change its steepness. These changes alter the equation accordingly.

Interpreting Graph Shifts and Reflections

A graph shifted left by h units and down by k units corresponds to g(x + h) - k. A reflection across the x-axis changes the sign of the function, resulting in -g(x). Recognizing these shifts and reflections from the graph helps write the transformed function's equation.

Recommended video:

4:25

Graphs of Shifted & Reflected Functions

Related Practice

Textbook Question

The graph of a function ƒ is shown in the figure. Sketch the graph of each function defined as follows.

Textbook Question

The graph of a function ƒ is shown in the figure. Sketch the graph of each function defined as follows.

(a) y = ƒ(x) +3

Textbook Question

Let ƒ(x) = 3x -4. Find an equation for each reflection of the graph of ƒ(x). across the y-axis

Textbook Question

The graph of a function ƒ is shown in the figure. Sketch the graph of each function defined as follows.

(b) y = ƒ(x-2)

views

Textbook Question

For each function graphed, give the minimum and maximum values of ƒ(x) and the x-values at which they occur.

views

Textbook Question

Let ƒ(x) = 3x -4. Find an equation for each reflection of the graph of ƒ(x). across the x-axis