Ⅰ.
factorization
01 Factorization
02 Greatest common divisor and least common multiple

Ⅱ.
Integers and rational numbers
03 Integers and rational numbers
04 Calculation of rational numbers

Ⅲ.
equation
05 Use of characters and expressions
06 Solving linear equations
07 Application of linear equations

Ⅳ.
Graphs and proportions
08 Coordinate Plane and Graph
09 Proportionality and Inverse Proportion

1.
The optimal problem-solving textbook to reduce learning burden
It is structured to cover the essential concepts for each topic in detail and to allow sufficient practice of basic types.
By boldly omitting difficult content, questions that are rarely tested, or questions that do not fit recent test trends, we have reduced the learning burden and improved the learning achievement of students who struggle with math.

2.
Type segmentation
After covering all the easy school exam questions, we've broken them down into more specific types based on the concepts and solution methods needed to solve them, so you can learn problem-solving strategies for each type.

3.
three-dimensional learning
The difficulty of the problems is divided into two levels, A and B. By strengthening the basic problems of level A and further dividing the types of level B, three-dimensional learning is possible by level of difficulty and type.

4.
Perfect preparation for real-life situations
We have designed the final study questions for each unit based on frequently appearing questions in school exams to check the learning level of each unit, and we have also provided a final check through mock exams for each unit in the format of actual exam papers to ensure perfect preparation for the actual exam.

"Problem Basics Book Lightsen" reduces the burden on students who struggle with math, so they don't give up.

Choosing the right textbook for your level can help you improve your learning achievements.

To avoid dampening the motivation to learn due to difficult concepts and problems, we boldly omitted difficult problems that appear less frequently.

We also strengthened basic skills and improved problem-solving skills through type-specific learning.

Math type answer, Lightsen!
Lightsen is a problem-solving textbook optimized for students who struggle with math.