NCERT Solutions for Class 11 Maths Exercise 2.3 Relations and Functions in Hindi and English Medium updated for new academic session 2022-2023. If students are facing difficulties to understand the solutions through PDF, follow the video solutions given in Hindi and English Medium.

## NCERT Solutions for Class 11 Maths Exercise 2.3

### Domain and Range in Class 11 Maths Exercise 2.3

Class 11 Maths Exercise 2.3 is all about functions. In this section, you will understand the application of most of the concepts related to functions that you had learned till now. Implying the definition 5 (in NCERT Book), we can define it as a rule that links each element in one set, called the domain, to one element in another set, called the range. To know about relations, you must have understood the meaning of domain and range. If not, check the other examples’ definitions before proceeding to get in-depth knowledge of the functions and their different types.

#### Class 11 Maths Exercise 2.3 Types of functions

Since it is pretty and common that you are being introduced to functions, and then why would the book show you the example of function before this. For the some reason, the chapter urges you to look for the exampled 7 and 8 as they are not functions. Even the paragraph emphasized the specific reasons why these examples are not fulfilling the criteria of being a function.

Get an important fact to keep in mind as this might give you the idea to differentiate between relation and function. Though you are allowed to make the assumption that the purpose of revisiting example 7. It is to compare with examples 10 and 11. This may be the nicer way to look for the step taken in functions, facts of variables and functions.

##### About Class 11 Maths Exercise 2.3 Questions

Before proceeding to know about the long list of the functions f(x), we have to learn the basic functions given in NCERT book. One of the facts to keep in mind is that you can use any alphabet in both capital and lower case letter to show the functions and their variables. Like – g(t), h(x), f(s).

In exercise 2.3 only 5 questions are there based on the polynomial functions and their graphs. Here the main concentration of study is to find domain and range. Graph and its properties are a vital part of functions. Class 11 Maths Exercise 2.3 includes linear functions, quadratic functions, cubic function, and similar functions.

###### Importance of Constant functions

The definition of a constant function is not given there but it is well understandable with the help of a graph. With this, we can understand the linear function that has a constant and horizontal line in the Cartesian plane. More formally we can say that constant functions have the same range for different values of the domain.

The line is parallel to the x-axis. Here the point is any function that has y = k, the value to be considered as the constant. The concept is important, but if you understand the equations it will be much easier for you to recognize the function. Equation and values of the polynomials are something to pay attention to.  