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Derivative

The derivative is a function of a real variable that measures the sensitivity to change of the function value with respect to a change in its argument. Derivatives are a fundamental tool for finding maxima minima and for understanding the nature ‍of functions. It is widely used in business.

The derivative of a function of a real variable in mathematics describes the sensitivity of the function value to a change in its argument. Derivatives are a fundamental tool for finding maxima minima and for understanding the nature ‍of functions.

The derivative is a function itself; it describes in detail how much one quantity is changing in terms of another quantity. Its properties have many uses in mathematics and in other sciences, as well as in engineering.

 This article aims to teach you about derivatives and how they can be used to study transforming functions (both linear and nonlinear).

What is Derivative?

A derivative is a function that tells you how much one quantity is changing at a given point compared to another quantity.

The derivative is a fundamental concept of calculus. Intuitively, the derivative represents the rate of change or slope of the function at a given point. The derivative is defined as the limit of the difference quotient Δy/Δx as Δx approaches zero.

What is Derivative Formula?

The Derivative formula is used to find a derivative is known as Differentiation. The Formula for the Derivative is obtained for a variable ‘x’ having an exponent ‘y’. The exponent may be an integer or a Rational Fraction

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Rules of Derivative

There are some rules needed to be followed. These rules are the formulas that are used in the different levels and aspects of derivatives.

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Derivation of Derivative Formula

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Derivative Formula for the trigonometric function

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Types of the Derivative

A derivative is classified on the basis of the order

  • First Order
  • Second Order

First-Order Derivative

The first order derivatives indicate the direction of the function, that is, whether the function is increasing or decreasing. The first derivative maths or first-order derivative can be interpreted as an instantaneous rate of change. It can also be predicted from the slope of the tangent line at x = a. 

Second-Order Derivative

To acquire an understanding of the shape of the graph for a given function, second-order derivatives are used. Concavity can be used to categorize the functions.The concavity of the given graph function is classified into two types, namely, downward concave curve and upward concave curve. An inflection point is found where the first and second-order derivatives are zero (at the endpoints).

Applications of the Derivative

Derivatives are the rates at which the quantity is changing with respect to time. So, we have done integration to find the displacement from its velocity and from displacement to get the distance travelled by a body. Similarly, we use derivatives to find the rate of change of one quantity with respect to another quantity which is obtained by differentiating suitable functions.

Point of Inflection

If f ‘(x0) = 0 or f’”(x0) does not exist at points where f'(x0) exists and if f”(x) changes sign when passing through,

x = x0 then x0 is called the point of inflection.

  1. If f”(x) < 0, x ∈ (a, b), then it is concave Downward.
  2. if f” (x) > 0, x ∈ (a, b), then it is Concave Upward

In Real Life

  • check the temperature variation.
  • determine the speed or distance covered 
  • Deriving the Equations in Physics
  • study of Seismology like to find the range of magnitudes 
  • calculate the profit and loss in business

Approximation or Finding Approximate Value

Calculus uses derivatives to approximate any change in a quantity. If we need the rate of change, considering delta △ x as very small, the derivative gives this value.

dy/dx = △x = x.

Monotonicity

A function is called monotonic if it is either entirely increasing or entirely decreasing. That is to say that a monotonic function has the same sign throughout its entire domain. If a function is neither increasing or decreasing in its entire domain, then it is considered non-monotonic.

  • f'(x) will be positive when the function is increasing.
  • f'(x) will be negative when the function is decreasing.
  • f'(x) will be zero when the  function is at its maxima or minima.
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Frequently asked questions

Get answers to the most common queries related to the NDA Examination Preparation.

How to find a Derivative?

Ans : For finding the Derivative of the function y = f(x), We can use the Slope Formula:...Read full

What is the derivative in Finance?

Ans : Derivatives are financial contracts that derive their ...Read full

Is Derivative in maths and finance the same?

Ans : No, it is entirely different.

How are mathematical derivatives used in finance?

Ans : Derivatives are financial instruments that are used by investors to reduce the risk in the ma...Read full