The knowledge point of mathematical divisor and multiple in Xiaoshengchu is 1 1, and any common multiple of two numbers is a multiple of their least common multiple.

2. The product of the greatest common divisor and the least common multiple of two numbers is equal to the product of these two numbers.

The basic method of finding the least common multiple: 1, short division to find the least common multiple; 2. Method of factorizing prime factors

The basic method of finding the greatest common divisor;

1. prime factor decomposition: decompose prime factors first, and then multiply the same factors.

2, short division: first find the common divisor, and then multiply.

3, toss division: divide by divisor and remainder every time, and the remainder that can be divisible is the greatest common divisor.

Common multiple: the common multiple of several numbers is called the common multiple of these numbers; The smallest one is called the least common multiple of these numbers.

The multiple of 12 is: 12, 24, 36, 48 ...;

The multiple of 18 is: 18, 36, 54, 72 ...;

Then the common multiples of 12 and 18 are: 36,72,108 ...;

Then the least common multiple of 12 and 18 is 36, and it is recorded as [12, 18]=36.

The above are the knowledge points of math divisor and multiple in junior high school prepared by math network, I hope it will help you.

Knowledge points of mathematical divisor and multiple in multiples and divisors of Xiaoshengchu 2

Maximum common divisor: The common divisor of several numbers is called the common divisor of these numbers. There is a finite common factor. The largest one is called the greatest common divisor of these numbers.

Least common multiple: The common multiple of several numbers is called the common multiple of these numbers. There are infinite common multiples. The smallest one is called the least common multiple of these numbers.

Prime number: the common divisor has only 1 two numbers, which is called prime number. Two adjacent numbers must be prime numbers. Two consecutive odd numbers must be coprime. 1 and any number coprime.

Comprehensive score: the difference between scores of different denominators is changed into the same denominator score equal to the original score, which is called comprehensive score. (Common divisor is the least common multiple)

Decrement: divide the numerator and denominator of a fraction by the common divisor at the same time, and the fraction value remains unchanged. This process is called dropping points.

Simplest fraction: The numerator and denominator are fractions of prime numbers, which are called simplest fraction. At the end of the score calculation, the score must be converted into the simplest score.

Prime number (prime number): If a number only has 1 and its two divisors, it is called a prime number (or prime number).

Composite number: a number. If there are other divisors besides 1 and itself, such numbers are called composite numbers. 1 is neither prime nor composite.

Prime factor: If a prime number is a factor of a certain number, then this prime number is the prime factor of this number.

Prime factor decomposition: A composite number is represented by the complementary way of prime factors, which is called prime factor decomposition.

Multiple characteristics:

Characteristics of multiples of 2: You are 0, 2, 4, 6, 8.

Characteristics of multiples of 3 (or 9): The sum of the numbers on each digit is multiples of 3 (or 9).

Characteristics of multiples of 5: You are 0, 5.

Characteristics of multiples of 4 (or 25): The last two digits are multiples of 4 (or 25).

Characteristics of multiples of 8 (or 125): the last three digits are multiples of 8 (or 125).

Characteristics of multiples of 7 (1 1 or 13): the difference (big-small) between the last three digits and other digits is a multiple of 7 (1 1 3).

Characteristics of multiples of 17 (or 59): the difference (big-small) between the last three digits and the rest digits is a multiple of 17 (or 59).

Characteristics of multiples of 19 (or 53): the difference (big-small) between the last three digits and other seven digits is a multiple of 19 (or 53).

Characteristics of multiples of 23 (or 29): The difference (big-small) between the last four digits and the other five digits is multiples of 23 (or 29).

Of the two numbers in the multiple relation, the greatest common divisor is smaller and the smallest common multiple is larger.

The coprime relation between two numbers, the greatest common divisor is 1, and the least common multiple is the product.

When two numbers are divided by their greatest common divisor, the quotient is coprime.

The product of two numbers and the least common multiple is equal to the product of these two numbers.

The common divisor of two numbers must be the greatest common divisor of these two numbers.

1 is neither prime nor composite.

A prime number greater than 3 divided by 6 must get 1 or 5.

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