Matrices are a relatively simple topic. The patterns for solving problems are uncomplicated and don’t require much knowledge, just what you’ve learned in middle school, or perhaps even elementary school.
However, there’s one issue associated with them – to compute something as silly as the rank of a matrix or even a determinant of a low order, you really need to perform a lot of mathematical operations.
Computational Errors in Solving Problems
Simple ones – like adding and multiplying positive and negative numbers, but there are many to carry out – maybe dozens, or even hundreds. Thus, it’s easy to make a computational error such as this 
, and one such blunder can ruin the entire problem.
Everyone has their own rate of simple computational errors, and for every hundred straightforward operations, a few mistakes are made. It’s normal and it doesn’t go away with age. “Silly mistakes” will always accompany us. However, this rate can and should be lowered.
Solution
One way is to solve a large number of matrix problems (this really helps), and another is to write down all calculations in tiny print on the margin or in a rough draft.
When multiplying matrices, write it down. When adding rows while calculating a matrix determinant, write it down. Do not try to compute 
in your head. You’ll see that your visual memory is your best friend.
Good luck with your matrix calculations!
This will also definitely be helped by my dedicated course – Matrix Course 🙂
