moving target

1, understand the structure of division formula and division symbol.

2. Let the children divide a number into two parts, correctly calculate the divisor formula, and correctly write the format of the divisor formula in the small print book.

3. Educate children to keep quiet in the math contest, so as not to affect the thinking of the contestants.

Key points: Understand the division formula and calculate the division formula correctly.

Difficulty: Write the format of fraction form correctly in the math book (small print book).

Extended data

Additive essence

1 is exactly the same thing, that is, the repetition or accumulation of similar things, which is the beginning of numerical operation. Different kinds, such as an apple and an orange, can only be equal to two fruits, so there is a relationship between classification and classification. Subtraction is the inverse operation of addition; Multiplication is a special form of addition; Division is the inverse operation of multiplication; Power is a simple form of multiplication.

2. The root is the inverse operation of power; Logarithm is the law of finding power term; Derivative is developed from logarithm; Then differential and integral. The development of digital operation is a more special situation and a more repetitive law.

Introduction to addition

1, addition (usually indicated by the plus sign "+") is one of the four basic arithmetic operations, and the others are subtraction, multiplication and division. For example, in the picture below, * * * has a combination of three apples and two apples, and * * * counts as five apples. This observation is equivalent to the mathematical expression "3+2 = 5", that is, "3 plus 2 equals 5".

2. In arithmetic, the addition rules involving fractions and negative numbers are designed.

3. Addition has several important attributes. It is interchangeable, which means that the order is not important, it is interrelated, which means that when more than two numbers are added, the order in which the addition is performed is not important. Repeatedly adding 1 is the same as counting; Adding 0 will not change the result. Addition also follows related operations such as subtraction and multiplication.

4. Addition is one of the simplest digital tasks. The most basic addition: 1+ 1 five-month-old babies and even other animal species can be counted. In primary education, students are taught to calculate the superposition of decimal numbers, starting with one digit, and gradually solving the more difficult number calculation.

References:

Baidu Encyclopedia-Supplement