NCERT Solutions for Class 12 Maths Chapter 4 Exercise 4.2 Determinants in Hindi and English Medium updated for CBSE 2023-2024. Class 12th Maths Ex. 4.2 is updated for new session 2023-24 as per the rationalised syllabus.

## Class 12 Maths Exercise 4.2 Solution in Hindi and English Medium

### NCERT Solutions for Class 12 Maths Chapter 4 Exercise 4.2

Ex. 4.2 solutions for 12th Math is applicable for UP Board, CBSE Board (Uttarakhand and Bihar Board and other board also, who are using NCERT Books as course books. Videos related to each question are also given here. Properties of determinants are used perfectly whenever it is required in the questions. Questions are done using simplified steps, so that each student can understand the steps of solutions. 12th Maths Exercise 4.2 Solutions are divided in four videos. The first videos show the solutions of question 1, second video is for questions 2 and 3. Next two videos are prepared for Exercise 4.2 Question 4 and 5. All the study material on Tiwari Academy is free to use. If you are facing any difficulty to access these online contents, please contact us for help.

Class: 12 | Mathematics |

Chapter 4: | Exercise 4.2 |

Chapter Name: | Determinants |

Session: | CBSE 2023-24 |

Content Type: | Text and Videos Format |

Medium: | English and Hindi Medium |

#### 12th Maths Exercise 4.2 Solutions

NCERT Solutions for Class 12 Maths Chapter 4 Exercise 4.2 Determinants based on the concept of area of triangle, co-linear points and equation of lines using determinants. NCERT Solutions based on NCERT textbooks for 12th are given in Hindi and English medium. You can take help for NIOS board also.

##### More about Determinants

If the points are co-linear, the triangle can’t be formed. So, in case of collinear points, we put area of triangle zero to solve the questions. Similarly, if we have to find a equation of a line through two given points using determinants, we will assume a third general points(x, y) on the line joining the two point, which will make the three points collinear and then apply the formula of area of triangle put it equal to zero.

Always prefer the formulae which are given in NCERT Books. For any suggestion related to NCERT solutions or online contents of CBSE or NIOS, please contact us though discussion forum.

### Important Questions of 12th Maths Exercise 4.2

### Why do we take absolute value of determinant during finding area?

Since area is a positive quantity, we always take the absolute value of the determinant.

### What is the meaning of a determinant?

For every square matrix associated to a real number, which is called the determinant of the matrix.

### How do we find the determinant of a matrix?

For a 2×2 matrix, we can directly find the determinant using just cross multiplication and subtracting the result. For, a 3×3 matrix, expand the matrix along a row or a column with its co-factors.

### What is the difference between matrices and determinants?

Matrix is the way to represent elements in tabular format whereas the determinants is a number associated to a square matrix.

###### Area of Triangle in 12th Maths Exercise 4.2

Tribhuj ka kshetraphal chaahe dhanaatmak ho ya rnaatmak, ham use hamesha dhanaatmak hee lenge. kyonki tribhuj ka kshetraphal kabhee rnaatmak nahin ho sakata. yadi kisee prashn mein tribhuj ka kshetraphal diya hua hai to us maan to rnaatmak tatha dhanaatmak donon se hal karenge. sanrekh binduon se koee tribhuj nahin ban sakata hai atah inase banane vaale tribhuj ka kshetraphal shoony hoga. kaksha 12 ke paath 4 kee prashnaavalee 4.2 ke hal jo tribhuj ke kshetraphal, sanrekh binduon aur saral rekha ke sameekaran par aadhaarit hai.

### What are the main points that students should know before starting exercise 4.2 of class 12th Maths?

The main points that students should know before starting exercise 4.2 of class 12th Maths are:

- 1. Area of a Triangle

In earlier classes, we have studied that the area of a triangle whose vertices are (x₁, y₁), (x₂, y₂) and (x₃, y₃) is given by the expression

Now this expression can be written in the form of a determinant as - 2. Since the area is a positive quantity, we always take the absolute value of the determinant in (1).
- 3. If the area is given, use both positive and negative values of the determinant for calculation.
- 4. The area of the triangle formed by three collinear points is zero.

### Which problems of exercise 4.2 of grade 12th Maths have chances to come in the board exam?

Exercise 4.2 of 12th standard Maths has two examples (examples 17, 18) and five questions. All the examples and questions of this exercise are significant from an exam point of view. However, questions 2, 3, 4, 5, and example 18 are most important and have more chances to come in the board exams than other questions of exercise 4.2 of class 12th Maths.

### Is exercise 4.2 of chapter 4 Class 12th Maths lengthy?

No, exercise 4.2 of chapter 4 of class 12th Maths is not at all lengthy. Only two examples (examples 17, 18) and five questions are there in exercise 4.3. Students need a maximum of 2 days to do exercise 4.2 if they give 1 hour per day to this exercise. It is an approximate time, and this time can vary because no two students can have the same working speed.

### Is exercise 4.2 of class 12th Maths simple to solve?

Yes, exercise 4.2 of class 12th Maths is very simple to understand and solve. Most of the students quickly solve all problems of this exercise. However, the difficulty level varies from child to child. So, exercise 4.2 of class 12th Maths is simple or complex depends on children also. Some children find it difficult, some find it easy, and some find it in the middle of easy and difficult.