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Differential Equations – Important Questions

A differential equation involves the derivatives of one or more independent variables and a dependent variable. Read on for an overview of differential equations.

A differential equation is an equation that includes the derivative of an unknown function. To determine how quickly a function changes at a given point, one must look at its derivatives. Through a differential equation, the derivatives of these functions are linked together.

Differential equations have two types of solutions: general and particular. Integration is used in both the general and particular solutions of differential equations. Differential equations can be solved in one of five ways. Let’s look at some differential equations and their important questions.

How to Solve Differential Equations

Now that you know what a differential equation is, let us look at how to find a solution to them.

Approaches to solving differential equations

  • Solution by inspection 
  • Variable separable
  • Homogeneous
  • Linear differential equation
  • General

To solve a differential equation, we use y = f(x), where f(x) is the function that yields the solution. 

The differential equation has both a general and a particular solution. Changing the arbitrary constant values in the general solution leads to a particular solution. The general solution has arbitrary constants in it.

The general solution of differential equations

The solution to an nth-order differential equation that includes n significant arbitrary constants is a general solution of the differential equation.

Using a variable method to solve a first-order differential equation, we must introduce an arbitrary constant when integration is complete. As a result, the solution to the first-order differential equation contains an important arbitrary constant after simplifying. Similarly, the general solution of a second-order differential equation includes important arbitrary constants, and so on. 

The general solution is geometrically equivalent to an n-parameter family of curves. For example, the general solution to differential equation dy/dx = 8x2  is found to be y = x3 + C, where c is an arbitrarily chosen coefficient.

How to find solutions to differential equations

The values, equations, curves, and lines that satisfy the given differential equation are known as solutions. Solutions to the simple equation of the form x2 + 4 = 0 or sin2x + cosx = 0 can be expressed as numeric values, whether real or complex. 

The solution to an equation can be substituted for x in the equation, and the equation’s left-hand side is equal to the right-hand side.

Let’s look at the differential equation d2y/dx2 + y = 0 in more depth. It is possible to solve a differential equation by drawing a curve of the form: y = f(x), where x is the variable that is a function of y. When the answer y = f(x) is used in the differential equation’s solution, the left and right sides are equal.

The solution to a differential equation is infinite. In mathematics, finding the solution to a differential equation is called integrating a differential equation. A differential equation solution is an expression for the dependent variable in terms of the independent variable that meets the differential equation’s conditions. 

The general solution is the one with the most arbitrary constants. A particular solution is what we get when we give specific values to the arbitrary constants in the differential equation’s general solution. 

For example, a first-order differential equation is formed by removing one arbitrary constant, while a second-order differential equation is formed by removing two arbitrary constants. 

Particular solutions and general solution of a differential equation

The universal solution of a differential equation is a function f(x) with any number of constants, such as a and b, as inputs. A solution to the differential equation that does not include an arbitrarily given constant is called a particular solution.

  • Differential equation: d2y/dx2 + 2dy/dx + 1 = 0
  • General solution: y = 2x + k
  • Particular solution: y = 2x + 2, y =2x + 7

It is called the general solution to the differential equation if it contains any arbitrary values and represents the family of curves in the coordinate system. It is also possible to refer to the solution without arbitrary constants as “the particular solution of a differential equation” and the general solution as “the particular solution of a differential equation” when the constants are given values.

Conclusion

Getting an overview of differential equations and their important questions is required to understand the deep concepts of calculus. In addition, these equations have a vast scope and use in architecture and material science. Through this topic, you can learn to find the solution of differential equations.

Mathematicians use derivatives to express rates of change in calculus. Sometimes, the solutions to these equations reveal how and why specific variables change.

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What are the solutions to a differential equation?

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