Preface:
This problem book is designed for people who are concerned about their intellectual health. After all, modern life requires that our minds be constantly in shape. But how to maintain your mind in a fairly effective state, that is, how to maintain your memory and your mind, that is, “thinking”? There are many such ways: solving scanwords, crosswords, solving puzzles. Scanword puzzles and crossword puzzles help boost your memory, help develop your horizons, and puzzles train your mind well. I suggest solving mathematical matrices, this is a very good way to train your memory and train your mind. Below is an example of solving mathematical matrices. The rules for solving them will also be outlined, discussed with an example. Of course, you can, if you know how to solve matrices, solve them in your own way, but I still recommend solving matrices according to two rules:
1) Try to do all actions in your mind, write only intermediate results.
2) Solve matrices, only one per day
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