1, basic concept: definition of rational number: general designation of integer and fraction. Integer: including positive integer, zero and negative integer. Fraction: the result of dividing the numerator by the denominator.

2. number axis and rational number: the concept of number axis: a one-dimensional straight line used to represent a group of real numbers. The position of rational number on the number axis. Positions of positive numbers, negative numbers and zeros.

3. Antiquities: Definition: Only two numbers with different symbols are opposite. Representation on the number axis.

4. Absolute value: definition: the distance from the origin (whether positive or negative). Rules for calculating absolute values. Geometric meaning of absolute value.

5. Algorithm: addition: add two numbers with the same symbol: take the same symbol and add the absolute values. Add two numbers with different signs: if the absolute values are equal, the result is 0; If the absolute values are not equal, take the sign of the number with the larger absolute value and subtract the smaller absolute value from the larger absolute value.

6. Subtraction: Convert to addition. Multiplication: any number multiplied by 0 equals 0; Two numbers with the same sign are positive when multiplied, and two numbers with different signs are negative when multiplied; Multiply the absolute values. Division: cannot be divided by 0; Divide by the reciprocal.

7. Comparison size: comparison with the same number: the greater the absolute value, the greater the number. Comparison of different symbols: positive numbers are greater than negative numbers, and negative numbers with larger absolute values are smaller. Operation law and association law.

8. When creating a mind map, please make sure that each node clearly represents the key information of knowledge points, and use arrows or branches to connect related concepts to facilitate visualization and understanding of these relationships. At the same time, we can consider using visual elements such as colors and icons to enhance the memory effect.

9. Creating a mathematical mind map is a process of visualizing mathematical concepts, formulas and relationships, which is helpful to remember, understand and organize complex mathematical knowledge. Share your mind map, communicate with classmates or teachers, and maybe you will have new insights and understanding. You can create a clear and intuitive mathematical mind map to help you master mathematical knowledge better.