first derivative

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first derivative

A student calculates the first derivative of a function on a chalkboard.

Definition
  1. Noun:
    • The result of mathematical differentiation: The "first derivative" is the fundamental outcome of the differentiation process in calculus. It represents the rate at which a function's output value changes as its input value changes.
    • Instantaneous rate of change: It measures the exact, instantaneous change of one quantity (the dependent variable) relative to a change in another quantity (the independent variable).
    • Formal notation: Commonly denoted as ( f'(x) ), ( \frac{dy}{dx} ), or ( \frac{df(x)}{dx} ).
Usage Examples
  • Noun:
    • To find the slope of the tangent line at any point on the curve, you must calculate the first derivative of the function.
    • The first derivative of the position function with respect to time gives the object's velocity.
    • Setting the first derivative equal to zero helps identify critical points, which can be local maxima or minima.
Advanced Usage
  • "First derivative test": A method in calculus used to determine whether a critical point of a function is a local maximum, local minimum, or neither, by analyzing the sign of the first derivative before and after that point.

    • We applied the first derivative test to classify the critical points of the polynomial.
  • "First derivative of a vector function": The derivative of a vector-valued function, which results in another vector representing the instantaneous rate of change.

    • The first derivative of the path vector gives the velocity vector of the particle.
Variants and Related Words
  • Derivative (n): A more general term. The "first derivative" is a specific type of derivative. Higher-order derivatives (e.g., second derivative, third derivative) are found by repeatedly differentiating the function.

    • The second derivative is found by taking the derivative of the first derivative.
  • Differentiation (n): The mathematical process or operation used to find a derivative.

    • The first derivative is obtained through the process of differentiation.
  • Differential calculus (n): The branch of calculus concerned with derivatives and their applications.

Synonyms
  • Rate of change function
  • Differential coefficient (a less common, more formal term)
  • Gradient (commonly used in multivariable contexts for the vector of first partial derivatives)
Related Phrases
  • Take the first derivative: To perform the differentiation operation.

    • The first step is to take the first derivative of the given equation.
  • With respect to (w.r.t.): A phrase specifying the independent variable for differentiation, crucial for defining the first derivative.

    • Find the first derivative of the function *f with respect to x.*
Related Concepts
  • Slope: The geometric interpretation of the first derivative at a point is the slope of the tangent line to the function's graph at that point.

    • The first derivative at x=2 represents the slope of the curve at that specific point.
  • Instantaneous velocity: A key physical application where the first derivative of position with respect to time equals instantaneous velocity.

first derivative

A student calculates the first derivative of a function on a chalkboard.

Noun
  1. the result of mathematical differentiation; the instantaneous change of one quantity relative to another; df(x)/dx