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  1. increasing and decreasing intervals
    Decreasing intervals are ranges of input values where a function's output values decrease as the input values increase, indicating a negative slope in that interval.

    Definition of Decreasing Intervals

    A function \(f(x)\) is said to be decreasing on an interval \(I\) if, for any two points \(x_1\) and \(x_2\) in that interval, where \(x_1 < x_2\), the following condition holds:
    \[ f(x_1) \geq f(x_2) \]

    Identifying Decreasing Intervals

    To determine the decreasing intervals of a function, you can use the first derivative test. Here’s how it works:
    1. Find the Derivative: Calculate the first derivative \(f'(x)\) of the function.
    2. Analyze the Sign of the Derivative:

    Example

    Consider the function \(f(x) = x\^3 - 3x\^2 + 2\). To find the decreasing intervals:
    1. Calculate the Derivative: \(f'(x) = 3x\^2 - 6x\).
    2. Set the Derivative to Zero: Solve \(3x\^2 - 6x = 0\) to find critical points. This gives \(x = 0\) and \(x = 2\).
    3. Test Intervals: Choose test points in the intervals \((-∞, 0)\), \((0, 2)\), and \((2, ∞)\):

    Importance of Decreasing Intervals

    Cuemath
    Increasing and Decreasing Intervals - Definition, Formulas, Examples
    Increasing and decreasing intervals are intervals of real numbers where the real-valued functions are increasing and decreasing respectively. To determine the increasing and decrea…
    GeeksForGeeks
    Increasing and Decreasing Intervals - GeeksforGeeks
    Increasing and decreasing intervals are the intervals of real numbers in which real-valued functions are increasing and decreasing respectively. Derivatives are a way of measuring …
    Lumen Learning
    Use a graph to determine where a function is increasing, decreasing, or ...
    As part of exploring how functions change, we can identify intervals over which the function is changing in specific ways. We say that a function is increasing on an interval if th…
    Math is Fun
    Increasing and Decreasing Functions - Math is Fun
    Learn how to identify and graph functions that are increasing or decreasing on an interval. See examples, definitions, and algebraic tests for increasing and decreasing functions.
    GreeneMath.com
    Increasing, Decreasing, and Constant Intervals Lesson
    In this lesson, we want to learn how to determine where a function is increasing, decreasing, or constant from its graph. Let's begin with something simple, the linear function. We…
  1. Increasing and Decreasing Intervals - Definition, …

    If the first derivative of a function is positive in an interval, then it is said to be an increasing interval and if the first derivative of the function is negative …

  2. Increasing and decreasing intervals | Definition, Formula & Examples

    Oct 22, 2025 · Learn about increasing and decreasing intervals with clear definitions, step-by-step explanations, and examples to help you understand and master this concept easily.

  3. Increasing and Decreasing Intervals - GeeksforGeeks

    Jul 23, 2025 · The interval of region will increase if the value of the function f (x) increases with an increase in the value of x and it will decrease if f (x) …

  4. Mastering Increasing and Decreasing Intervals

    Learn how to determine where college algebra functions increase or decrease by identifying intervals. Includes clear steps and examples.

  5. Increasing and Decreasing Functions - Math is Fun

    Learn how to identify and graph functions that are increasing or decreasing on an interval. See examples, definitions, and algebraic tests for increasing and decreasi

    A function is "increasing" when the y-value increases as the x-valueincreases, like this: It is easy to see that y=f(x) tends to go up as it goes along.
    See more on mathsisfun.com
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  7. Increasing and Decreasing Functions - CK-12 …

    Dec 1, 2025 · Identify the intervals of increase and decrease, use interval notation: The function increases on the interval (∞, 1) and on the interval …

  8. Increasing & decreasing intervals review (article) - Khan Academy

    Review how we use differential calculus to find the intervals where a function increases or decreases.

  9. Increasing and Decreasing Intervals of Functions Explained

    A decreasing interval is a portion of the domain of a function where as x increases, the value of the function f (x) decreases. Mathematically, for any two numbers x₁ < x₂ in the interval, f (x₁) > f …

  10. Increasing and Decreasing Intervals of a Function: A …

    Learn how to identify increasing and decreasing intervals using the first derivative to analyze function behavior in AP® Calculus AB-BC.

  11. Increasing, Decreasing, and Constant Intervals Lesson

    In this lesson, we want to learn how to determine where a function is increasing, decreasing, or constant from its graph. Let's begin with …