Math Problem Statement

Use technology to find points and then graph the function y, equals, minus, 2, vertical bar, x, minus, 1, vertical bar, minus, 2, commay=−2∣x−1∣−2, following the instructions below.

Solution

To graph the function y=2x12y = -2 |x - 1| - 2 and find key points, we can break the process into the following steps:

Step 1: Rewrite the Equation

The given equation is: y=2x12y = -2 |x - 1| - 2 This is a transformation of the absolute value function y=xy = |x|.

  • The term x1|x - 1| indicates a horizontal shift 1 unit to the right.
  • The multiplication by -2 indicates a vertical stretch by a factor of 2 and a reflection across the x-axis.
  • The constant -2 at the end indicates a vertical shift 2 units down.

Step 2: Key Points Calculation

We will find a few key points by plugging in values for xx and solving for yy:

  1. Vertex: The vertex of the absolute value function occurs when x=1x = 1 because x1=0|x - 1| = 0 at x=1x = 1.

    • When x=1x = 1, y=2112=2(0)2=2y = -2 |1 - 1| - 2 = -2(0) - 2 = -2.
    • So the vertex is (1,2)(1, -2).
  2. Other points: Now, let's calculate yy for a few other values of xx:

    • When x=0x = 0, y=2012=2(1)2=4y = -2 |0 - 1| - 2 = -2(1) - 2 = -4.

    • So the point is (0,4)(0, -4).

    • When x=2x = 2, y=2212=2(1)2=4y = -2 |2 - 1| - 2 = -2(1) - 2 = -4.

    • So the point is (2,4)(2, -4).

    • When x=1x = -1, y=2112=2(2)2=6y = -2 |-1 - 1| - 2 = -2(2) - 2 = -6.

    • So the point is (1,6)(-1, -6).

    • When x=3x = 3, y=2312=2(2)2=6y = -2 |3 - 1| - 2 = -2(2) - 2 = -6.

    • So the point is (3,6)(3, -6).

Step 3: Graphing the Function

The points we have found are:

  • Vertex: (1,2)(1, -2)
  • (0,4)(0, -4), (2,4)(2, -4)
  • (1,6)(-1, -6), (3,6)(3, -6)

The graph will have a "V" shape, opening downward due to the negative coefficient of the absolute value term. The vertex is at (1,2)(1, -2), and the function decreases symmetrically away from this point.

Step 4: Graph Description

To graph this function:

  • Plot the vertex at (1,2)(1, -2).
  • Plot additional points such as (0,4)(0, -4), (2,4)(2, -4), (1,6)(-1, -6), and (3,6)(3, -6).
  • Draw a V-shaped graph that opens downward, with symmetry about the vertical line x=1x = 1.

Graph Example:

    y
    ^
  -6|   .       .               .       .
  -5|
  -4|     .   .                   .   .
  -3|
  -2|        V
  -1|
   0|-----------------------------> x
      -3 -2 -1  0   1   2   3

Would you like a detailed graph drawn, or any additional information about the steps above?


Here are 5 related questions to expand your understanding:

  1. How does changing the coefficient of the absolute value function affect the graph?
  2. What happens if we replace x1|x - 1| with x+1|x + 1|?
  3. How do vertical and horizontal shifts impact the symmetry of the graph?
  4. Can you graph a similar equation, such as y=3x2+1y = 3 |x - 2| + 1?
  5. How would the graph change if we applied a horizontal stretch to x1|x - 1|?

Tip: Always identify the vertex of the absolute value function first, as it defines the key point of symmetry.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Absolute Value Functions
Graph Transformations
Algebra

Formulas

y = -2|x - 1| - 2

Theorems

Absolute Value Function Theorem

Suitable Grade Level

Grades 9-11