Rational Number Subtraction Concept 15, Rational Number Subtraction Concept

Adding a number is equal to subtracting the opposite of that number.

Addition and Subtraction of Rational Numbers" conceptual analysis.

1) Rational number addition rule:

That is, add two numbers with the same sign, take the same symbol, and add the absolute value. , add two numbers with unequal absolute values, take the additive sign with the larger absolute value, and subtract the smaller absolute value with the larger absolute value; Two numbers that are opposite to each other are added to give 0.

Add a number to 0 and still get this number.

2) The law of subtraction of rational numbers:

That is, subtracting a number is equal to adding the opposite of that number. The subtraction of rational numbers can be converted to addition.

Idea analysis] as long as you keep the various algorithms in mind.

And you can use it skillfully.

Do more exercises.

Problem Solving Process] 1.When the addition and subtraction of rational numbers is carried out, the subtraction can be converted into addition according to the subtraction law of rational numbers, which unifies the addition and subtraction of rational numbers into a single addition operation. At this point, it becomes the sum of several positive and negative numbers.

2.When converting mixed operations into addition operations, write algebraic sum, pay attention to the two different readings of algebra and form.

3.The form of the sum omitted from parentheses can be seen as an addition operation of rational numbers. Therefore, the addition law can be used to simplify the calculation, and attention should be paid to the rationality of the operation.

The definition of subtraction is to talk about the law of subtraction of rational numbers:

Subtracting a number is equal to adding the opposite of the number.

It is expressed by the formula: a-b=a+(-b).

The definition of rational number subtraction is: subtracting a number is equal to adding the opposite number of this number, where: two changes: subtraction operation becomes addition operation, subtraction becomes its opposite number, one constant: the subtracted number does not change, can be expressed as: a b=a+( b).

Rational numbers are a collective term for integers (positive integers, 0s, negative integers) and fractions, and are a collection of integers and fractions.

An integer can also be seen as a fraction of a denominator with a denominator. Real numbers that are not rational numbers are called irrational numbers, i.e., the decimal part of an irrational number is an infinite non-cyclic number. It is one of the important contents in the field of "number and algebra", which has a wide range of applications in real life, and is the basis for continuing to learn real numbers, algebraic formulas, equations, inequalities, Cartesian coordinate systems, functions, statistics and other mathematical content as well as related subject knowledge.

The Law of Addition of Rational Numbers:

Add two numbers of the same sign, take the same symbol, and add the absolute value of the two numbers of the different sign to the sum of 0 when the absolute value is equal (that is, the two numbers that are opposite to each other are added to get 0);

When the absolute value is unequal, take the sign of the number with the larger absolute value, and subtract the smaller absolute value from the larger absolute value

Add a number to 0 and still get this number.

The law of subtraction of rational numbers.

Subtracting a number is equal to adding the opposite of the number.

Want to know what is the law of the interchange of addition and subtraction in rational numbers?

a+b=a-(-b)

a-b=a+(-b)

Although you didn't ask ?

Add two numbers of the same sign, take the same symbol, and add the absolute value of the two numbers of the different sign to the sum of 0 when the absolute value is equal (that is, the two numbers that are opposite to each other are added to get 0);

When the absolute value is unequal, take the sign of the number with the larger absolute value, and subtract the smaller absolute value from the larger absolute value

Add a number to 0 and still get this number.

The law of subtraction of rational numbers.

Subtracting a number is equal to adding the opposite of the number.

Subtraction of Rational Numbers Subtracting a number is equal to adding the reciprocal of a number.

Subtracting a number is equal to adding the opposite of that number.

The definition of subtraction is to talk about the law of subtraction of rational numbers:

Subtracting a number is equal to adding the opposite of the number.

It is expressed by the formula: a-b=a+(-b).

(-72) minus (-37) minus (-22) minus seventeen ==-72 + 37 + 22

16) minus (-12) minus 24 minus (-18).

23 minus (-76) minus 36 minus (-105).

32) minus (-27) minus (-72) minus 87

Subtracting a number is equal to adding the opposite of that number.

The law of subtraction of rational numbers: subtracting a number is equal to adding the opposite of the number. Among them: two variations: subtraction becomes addition, and subtraction becomes its opposite. One constant: the subtracted number does not change. It can be expressed as:

a－b=a+（－b）。

If —x+(—then x= 9

a= b= c=

a-b+c=

The third is negative.