Matrices is a fairly easy chapter for most students. Being a math educator for close to 3 decades, I am presenting a few exam secrets for you to ace this chapter.
Matrices is usually clubbed with Determinants and questions on these are mixed together. In this blog, I would be focussing mainly on Matrices.
Be it the ISC or CBSE or State boards, Matrices form an important part of questioning.That is to say, the weightage is good in the question paper.
To start with you need to know what is a matrix and the order of a matrix.
Then you need to know how to add or subtract matrices and scalar multiplication . These are topics taught in the ICSE curriculum for class 10. However, CBSE students may have to learn this for the first time. This is usually asked as objective questions.
Then you need to know about scalar matrix, diagonal matrix, identity matrix. Lots of objective questions could be asked on this topic.
Matrix multiplication is the next topic you need to master. You need to remember that you can multiply 2 matrices only if the number of columns of the first = the number of rows of the second. A number of problems can be asked from this topic , both long answer and objective.
Finally, you need to know inverse of a matrix and its existence. For Class 12 students, you need to know how to find the inverse of a matrix using elementary row and column operations. Remember, while finding the inverse using row operations, we write A= IA, where A is any matrix and while finding the inverse using elementary column operations, we write A=AI.
In my opinion, this is the only difficult part of this chapter. Time and again, students have asked me to teach them this concept over and over again. Each problem is different, there is no unique method and it is so easy to miss the right answer. It might help to remember that while using elementary row operations, make the lower triangle zero, while using elementary column operations, make the upper triangle zero. I am attaching a video which may help you in understanding this topic.
Be prepared for MCQ'S and objective based questions and CBSE students , be prepared for case study questions, where you need to form a matrix from the data given. Once you do that, the rest falls in place. Only make sure that matrix multiplication is satisfied.
Most important, write and practice the problems.
Do you find matrix multiplication easy?
For any queries, email me on firstname.lastname@example.org