Before we begin to explain, let's make clear the definition of rational number. Rational number is a special real number, including integer and fraction. Integers can be expressed as fractions with both numerator and denominator of 0, while fractions can be expressed as fractions with both numerator and denominator of positive integer or 0.

For example, 4 is a rational number and can be expressed as a fraction of 14. The same,? 3 is also a rational number, which can be expressed as a fraction of 1? 3。 Rational number is the basis of mathematics, and mastering the operation of rational number is very important for learning mathematics.

Next, we begin to explain rational number subtraction. The rational number subtraction can be calculated by the following steps:

First, the absolute values of two rational numbers are subtracted. For example, we have to count 5? 3, we can directly calculate 5? 3=2。

If the sign of the minuend is the same as the sign of the minuend, then the result is positive. If the sign of the minuend is different from the sign of the minuend, the result is negative. For example, we have to calculate? 5? 3, can we calculate the absolute value of 5 first? 3=2, and then because the signs of the minuend and the minuend are different, what is the result? 2。

In addition to addition calculation, we can directly calculate the result of absolute value addition without considering the sign, and then add the signs of the results. For example, we have to calculate? 5+3, we can first calculate the absolute value of 5+3=8, and then because the signs of the minuend and the minuend are different, what is the result? 8。

Through the above explanation, I believe you have understood the basic method of rational number subtraction. In rational number subtraction, we need to subtract the absolute value and determine the sign of the result according to the sign of the minuend and the minuend.

In addition, we can directly calculate the result of absolute value addition without considering the sign, and then add the signs of the results. Through constant practice and consolidation, I believe you will be able to master the operation method of rational number subtraction.

Expand knowledge:

In rational number subtraction, we need to pay attention to the following points:

In rational number subtraction, we need to subtract the absolute value and determine the sign of the result according to the sign of the minuend and the minuend.

When adding rational numbers, you can directly calculate the result of absolute value addition regardless of the sign, and then add the signs of the results.

The addition and subtraction operations of rational numbers are relatively basic contents in mathematics, and mastering these operations is very important for learning mathematics. In addition to addition and subtraction, you need to master other mathematical operations such as multiplication and division, exponent and radical.

When learning mathematics, we should pay attention to understanding the connotation and extension of mathematical concepts and avoid doing problems blindly. When doing a problem, you must first understand the meaning of the problem, and then answer it according to what you have learned. At the same time, we should pay attention to summarizing the methods and skills of doing problems.