Math Problem Statement

Consider the functions f(x) = -2(x - 3)^2 + 2 and g(x), which is represented by the graph. Describe key features such as increasing, decreasing, positive, and negative intervals for both f(x) and g(x).

Solution

Let's analyze the problem by focusing on both the given functions f(x)=2(x3)2+2f(x) = -2(x - 3)^2 + 2 and the graph for g(x)g(x).

1. Understanding f(x)f(x):

  • The function f(x)=2(x3)2+2f(x) = -2(x - 3)^2 + 2 is a parabola with the following properties:
    • Vertex: The vertex occurs at x=3x = 3, with f(3)=2f(3) = 2, meaning the vertex is (3,2)(3, 2).
    • Shape: Since the coefficient of (x3)2(x-3)^2 is negative (-2), the parabola opens downwards.
    • Increasing/Decreasing:
      • It is increasing on the interval (,3)(-\infty, 3).
      • It is decreasing on the interval (3,)(3, \infty).
    • Positive: The function is above the x-axis (positive) when f(x)>0f(x) > 0, which occurs between the roots of the equation. The roots are approximately at x=1x = 1 and x=5x = 5, so the function is positive on the interval (1,5)(1, 5).
    • Negative: The function is below the x-axis (negative) for x(,1)(5,)x \in (-\infty, 1) \cup (5, \infty).

2. Understanding g(x)g(x) from the Graph:

  • From the graph, g(x)g(x) is another parabola opening downwards, similar to f(x)f(x).
    • Vertex: The vertex seems to be at (0,2)(0, 2).
    • Increasing/Decreasing:
      • It is increasing on the interval (,0)(-\infty, 0).
      • It is decreasing on the interval (0,)(0, \infty).
    • Positive: The graph of g(x)g(x) is positive (above the x-axis) for (2,2)(-2, 2).
    • Negative: The graph of g(x)g(x) is negative (below the x-axis) for (,2)(2,)(-\infty, -2) \cup (2, \infty).

3. Assigning Intervals to Each Category:

f(x)f(x)g(x)g(x)
Increasing(,3)(-\infty, 3)(,0)(-\infty, 0)
Decreasing(3,)(3, \infty)(0,)(0, \infty)
Positive(1,5)(1, 5)(2,2)(-2, 2)
Negative(,1)(5,)(-\infty, 1) \cup (5, \infty)(,2)(2,)(-\infty, -2) \cup (2, \infty)

Feel free to ask for more details or explanations on any step!

Five relative questions:

  1. How do we find the vertex of a parabola in general?
  2. What is the significance of the parabola opening upwards or downwards?
  3. How do we determine whether a quadratic function is increasing or decreasing?
  4. How do we solve for the roots of a quadratic function like f(x)f(x)?
  5. How can we check if a function is positive or negative over an interval?

Tip:

Remember, a negative leading coefficient in a quadratic function always makes the parabola open downwards, indicating a maximum point at the vertex.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Quadratic Functions
Graph Analysis
Parabolas
Function Behavior

Formulas

f(x) = -2(x - 3)^2 + 2 (Standard form of quadratic function)
Vertex form of a parabola: y = a(x - h)^2 + k

Theorems

Vertex theorem for parabolas
Interval analysis for increasing/decreasing behavior

Suitable Grade Level

Grades 10-12